A
ABSCESS
An accumulation of pus in a body tissue, usually caused by a bacterial infection.
ACHILLES TENDON
The tendon at the back of the lower leg that connects the calf muscle to the heel bone.
ABO BLOOD GROUPS
The system by which human blood is classified, based on proteins occurring on red blood cells; the four classification groups are A, AB, B, and O.
ABORTION
Termination of a pregnancy; can occur because of natural causes (called a miscarriage) or be a medical intervention.
ACIDOSIS
A condition marked by abnormally high acid levels in the blood, associated with some forms of diabetes, lung disease, and severe kidney disease.
ACID REFLUX
A disorder in which acid in the stomach comes up into the esophagus, because the valve separating the stomach and esophagus does not function properly.
ACUTE
Describes a condition or illness that begins suddenly and is usually short-lasting.
ACUTE RESPIRATORY DISEASE
An urgent condition in which oxygen levels in the blood are lower than normal and breathing is difficult.
ADDICTION
Dependence on a substance (such as alcohol or other drugs) or an activity, to the point that stopping is very difficult and causes severe physical and mental reactions.
ADRENAL FAILURE
A condition in which the adrenal glands do not produce enough of the hormones that control important functions such as blood pressure.
ADRENAL GLANDS
Two small glands located on top of the kidneys that secrete several important hormones into the blood.
AIDS
Acquired immunodeficiency syndrome.
AIR EMBOLISM
The blockage of an artery by air bubbles, which may have entered during surgery or after an injury.
ALBINISM
A condition in which people are born with insufficient amounts of the pigment melanin, which is responsible for hair, skin, and eye color.
ALCOHOLIC CARDIOMYOPATHY
Heart damage and failure caused by intake of too much alcohol.
ALKALOSIS
Dangerously decreased acidity of the blood, which can be caused by high altitudes, hyperventilation, and excessive vomiting.
ALLERGEN
A substance that causes an allergic reaction.
ALLERGY
A negative reaction to a substance that in most people causes no reaction.
ALOPECIA
A baldness or loss of hair, mainly on the head, either in defined patches or completely; the cause is unknown.
ALZHEIMER DISEASE
A condition that occurs late in life and worsens with time in which brain.
CELLS DEGENERATE
It is accompanied by memory loss, physical decline, and confusion.
AMENORRHEA
Absence of menstrual periods, occurring either after or before menstruation has begun.
AMNIOTIC FLUID
Clear fluid that surrounds a fetus during pregnancy and cushions and protects it.
ANAL FISSURE
A long, open sore on the skin of the anus.
ANALGESIC
A drug that relieves pain, such as aspirin or acetaminophen.
ANAL SPHINCTER
A ring of muscle fibers at the opening of the rectum, controlling the opening and closing of the anus.
ANDROGEN
A hormone (such as testosterone) that causes development of male characteristics and sex organs.
ANEMIA
A condition in which the blood does not contain enough hemoglobin, the compound that carries oxygen from the lungs to other parts of the body.
ANESTHETIC
A substance that temporarily causes a person to be unable to feel pain, either in a certain area or over the entire body.
ANEURYSM
An abnormal swelling of the wall of an artery, caused by a weakening in the vessel wall.
ANGINA PECTORIS
Pain experienced in the chest, arms, or jaw because of a lack of oxygen to the heart muscle.
ANTIBIOTICS
Bacteria-killing substances that are used to fight infection.
ANTIBODY
An immunoglobulin molecule that reacts with a specific antigen that induced its synthesis. Synthesized by B lymphocytes that have been activated by the binding of a antigen to a cell surface receptor.
ANTIHISTAMINE
A drug that relieves an allergic reaction by stopping the effects of histamine, the substance responsible for the negative symptoms associated with the reaction.
ANUS
The opening through which feces are passed from the body.
AORTA
The main artery in the body, carrying oxygenated blood from the heart to other arteries in the body.
APPENDECTOMY
Surgical removal of the appendix to treat appendicitis.
ARTERY
A large blood vessel that carries blood from the heart to tissues and organs in the body.
ASPHYXIA
The medical term for suffocation; can be caused by choking on an object, by lack of oxygen in the air, or by chemicals such as carbon monoxide, which reduce the amount of oxygen in the blood.
ASTHMA
A disorder characterized by inflamed airways and difficulty breathing.
AUTISM
A mental disorder characterized by an inability to relate to other people and extreme withdrawal.
AUTOIMMUNE DISEASE
A disorder in which the body’s immune system attacks itself.
AUTOPSY
The examination of a body following death, possibly to determine the cause of death or for research.
AXILLA
Medical term for the armpit.
B
BACTEREMIA
A condition in which bacteria are present in the bloodstream; may occur after minor surgery or infection and may be dangerous for people with a weakened immune system or abnormal heart valves.
BACTERIURIA
Bacteria in the urine; large amounts can indicate bladder, urethra, or kidney infection.
BARIUM ENEMA
A technique in which barium is placed into the large intestine and rectum and then X-rays are taken to check for possible disorders of these organs.
B CELL
A white blood cell that makes antibodies to fight infections caused by foreign proteins.
BCG VACCINE
A vaccine used to protect against tuberculosis.
BENIGN TUMOR
A tumor that is not cancerous, which means it does not spread through the body, but may grow and become dangerous.
BILE
A yellow-green liquid produced in the liver whose function is to remove waste from the liver and break down fats as food is digested.
BILE DUCT
A tube that carries bile from the liver to the gallbladder and then to the small intestine.
BILIARY TRACT
The system of organs and ducts through which bile is made and transported from the liver to the small intestine.
BILIRUBIN
The orange-yellow pigment in bile, causing jaundice if it builds up in the blood and skin; the levels of bilirubin in the blood are used to diagnose liver disease.
BIRTH CANAL
The passage that includes the uterus and vagina through which the baby passes at birth.
BIRTH CONTROL
The regulation of the number of children born, referring either to the prevention of pregnancy (by birth control pill, sterilization, etc.) or the prevention of birth (by abortion, etc.).
BLADDER
An organ located in the pelvis whose function is to collect and store urine until it is expelled.
BLOOD CLOT
A semisolid mass of blood that forms to help seal and prevent bleeding from a damaged vessel.
BLOOD PRESSURE
The tension in the main arteries that is created by the beating of the heart and the resistance to flow and elasticity of the blood vessels.
BLOOD TRANSFUSION
The transfer of blood or any of its parts to a person who has lost blood due to an injury, disease, or operation.
Blood type
A category used to describe a person's blood according to the kinds of proteins present on the surface of the red blood cells.
B LYMPHOCYTE
A type of white blood cell that makes antibodies and is an important part of the immune response.
BONE MARROW
The fatty yellow or red tissue inside bones that is responsible for producing blood cells.
BONE MARROW TRANSPLANT
A surgical procedure in which defective or cancerous bone marrow is replaced with healthy marrow, either from the patient or a donor.
BONE SPUR
An abnormal growth of bone out of another bone, often located on the heel and usually painful.
BRADYCARDIA
A slow heart rate, usually below 60 beats per minute in adults.
BRAIN DAMAGE
Permanent death or damage of brain cells resulting in decreased mental ability.
BRAIN DEATH
The condition in which the brain stops functioning while the heart continues to beat.
BRONCHIOLITIS
An infection caused by a virus in the bronchioles (the smallest airways in the lungs), mainly affecting young children.
BRONCHODILATOR
A drug that widens the airways in the lungs to improve breathing; works by relieving muscle contraction or buildup of mucus.
BRONCHOSPASM
The temporary narrowing of the airways in the lungs, either as a result of muscle contraction or inflammation; may be caused by asthma, infection, lung disease, or an allergic reaction.
BYPASS
A surgical technique in which the flow of blood or another body fluid is redirected around a blockage.
C
CALCIFICATION
The depositing of calcium salts in the body, which occurs normally in teeth and bones but abnormally in injured muscles and narrowed arteries.
CALCITONIN
A hormone made in the thyroid gland that controls calcium levels in the blood by slowing the loss of calcium from bones; used to treat hypercalcemia (excess calcium in the blood).
CALCIUM
A plentiful mineral in the body and the basic component of teeth and bones; essential for cell function, muscle contraction, transmission of nerve impulses, and blood clotting.
CALCIUM CHANNEL BLOCKER
A drug used to treat chest pain, high blood pressure, and irregular heartbeat by preventing the movement of calcium into the muscle.
CANAL
A tunnel-like passage.
CANCER
A group of diseases in which cells grow unrestrained in an organ or tissue in the body; can spread to tissues around it and destroy them or be transported through blood or lymph pathways to other parts of the body.
CANDIDIASIS
A yeast infection caused by the fungus Candida albicans; occurs most often in the vagina, but also in the mouth, on moist skin, or on the penis.
CANKER SORE
Small, painful sore that usually occurs on the inside of the lip or cheek, or sometimes under the tongue; caused by bacteria, irritation of the area, stress, or allergies.
CAPILLARY
A tiny blood vessel that connects the smallest arteries to the smallest veins and allows exchange of oxygen and other materials between blood cells and body tissue cells.
CARBOHYDRATE
A substance, mainly sugar and starch, that is a main source of energy for the body and is found in sources such as cereals, breads, pastas, grains, and vegetables.
CARBON DIOXIDE
A colorless, odorless gas present in small amounts in the atmosphere and formed during respiration.
CARDIAC ARREST
The sudden cessation of the heart's pumping action, possibly due to a heart attack, respiratory arrest, electrical shock, extreme cold, blood loss, drug overdose, or a severe allergic reaction.
CARDIOGENIC SHOCK
A severely dangerous condition involving decreased blood output from the heart, usually as a result of a heart attack.
CARDIOMEGALY
A condition marked by enlargement of the heart, either because of a thickened heart muscle or an enlarged heart chamber; usually a result of the heart having to work harder than normal, as occurs with high blood pressure.
CARDIOMYOPATHY
A disease of the heart muscle that results in decreased output and reduced blood flow.
CARDIOVASCULAR SYSTEM
The heart and blood vessels that are responsible for circulating blood throughout the body.
CARDITIS
Inflammation of the heart.
CAROTID ARTERIES
Four main arteries that carry blood to the head and neck.
CARPAL BONES
Eight bones that together make the wrist.
CARTILAGE
A connective tissue (softer than bone) that is part of the skeletal system, including the joints.
CATHETER
A hollow, flexible tube inserted into the body to put in or take out fluid, or to open up or close blood vessels.
CATHETERIZATION
A technique in which a hollow, flexible tube is used to drain body fluids (such as urine), to introduce fluids into the body, or to examine or widen a narrowed vein or artery.
CELL
The tiny structures that make up all the tissues of the body and carry out all of its functions.
CELLULITIS
A skin infection caused by bacteria (usually streptococci); can lead to tissue damage and blood poisoning if untreated; characterized by fever, chills, heat, tenderness, and redness.
CENTRAL NERVOUS SYSTEM
The brain and spinal cord.
CEREBELLUM
A region of the brain located at the back; responsible for coordination of movement and maintaining balance.
CEREBRAL PALSY
A group of disorders of movement and posture resulting from damage to the brain early in a child's development; causes muscle weakness, difficulty coordinating voluntary movements, and sometimes complete loss of motion.
CEREBROSPINAL FLUID
A clear, watery fluid circulating in and around the brain and spinal column, which contains glucose, proteins, and salts for nutrition.
CEREBROVASCULAR DISEASE
A disease affecting any artery supplying blood to the brain; may cause blockage or rupture of a blood vessel, leading to a stroke.
CEREBRUM
The largest part of the brain and the site of most of its activity, including sensory and motor functions.
CERVICAL CAP
A small rubber cup that is placed tightly over the cervix to prevent pregnancy.
CERVICAL DYSPLASIA
Changes that occur in the cells on the surface of the cervix that usually precede the stages of cancer.
CERVICITIS
Inflammation of the cervix.
CERVIX
A small, round organ making up the neck of the uterus and separating it from the vagina.
CESAREAN SECTION
An operation performed to remove a fetus by cutting into the uterus, usually through the abdominal wall.
CHANCRE
A painless sore that has a thick, rubbery base and a defined edge; usually occurs on the genitals after the contraction of the sexually transmitted disease syphilis.
CHEMOTHERAPY
The treatment of infections or cancer with drugs that act on diseaseproducing organisms or cancerous tissue; may also affect normal cell.
CHICKENPOX
A contagious disease that causes a rash and a fever; most commonly occurs during childhood.
CHLAMYDIA
Microorganisms that cause several human infections and can be transmitted sexually.
CHOLECYSTECTOMY
The surgical removal of the gallbladder.
CHOLERA
A bacterial infection of the small intestine that causes severe watery diarrhea, dehydration, and possibly death.
CHOLESTEROL
A substance in body cells that plays a role in the production of hormones and bile salts and in the transport of fats in the bloodstream.
CHONDRITIS
Inflammation of cartilage.
CHONDROMA
A noncancerous tumor that occurs in cartilage.
CHRONIC
Describes a disorder that continues for a long period of time.
CLAUSTROPHOBIA
Fear of being confined in an enclosed or crowded space.
CLEFT LIP
A birth defect in which the upper lip is split vertically, extending into one or both nostrils.
CNS
Central nervous system.
COAGULATION
A process that plays a large role in the hardening and thickening of blood to form a clot.
COITUS
Sexual intercourse.
COLD SORE
A small blister anywhere around the mouth that is caused by the herpes simplex virus.
COLECTOMY
The complete or partial surgical removal of the large intestine (the colon), usually as treatment of a cancerous tumor or a narrowing and blockage of the intestine.
COLONOSCOPY
Investigation of the inside of the colon using a long, flexible fiberoptic tube.
COMA
A condition in which the area of the brain involved in maintaining consciousness is somehow affected, resulting in a state of unconsciousness in which the patient does not respond to stimulation.
COMMINUTED FRACTURE
A crushed or shattered bone.
COMMON COLD
An infection caused by a virus, which results in an inflamed lining of the nose and throat; characterized by a stuffy and runny nose and, sometimes, a sore throat.
CORONARY HEART DISEASE
Disorders that restrict the blood supply to the heart, including atherosclerosis.
CORONARY THROMBOSIS
The blockage of a coronary artery by a blood clot.
CREATININE
A waste product that is filtered from the blood by the kidneys and expelled in urine.
CT SCANNING
A procedure that uses X-rays and computers to create cross-sectional images of the body to diagnose and monitor disease.
CYSTECTOMY
Surgical removal of the bladder; the bladder is often replaced with a short length of small intestine.
D
DEHYDRATION
Excessive, dangerous loss of water from the body.
DEMENTIA
A gradual decline in mental ability usually caused by a brain disease, such as Alzheimer disease,
DEPRESSION
Feelings of hopelessness, sadness, and a general disinterest in life, which for the most part have no cause and may be the result of a psychiatric illness.
DERMATITIS
Inflammation of the skin.
DERMIS
The inner skin layer.
DETOXIFICATION
Treatment given either to fight a person's dependence on alcohol or other drugs or to rid the body of a poisonous substance and its effects.
DIABETES MELLITUS
A common form of diabetes in which the body cannot properly store or use glucose (sugar), the body's main source of energy,
DIALYSIS
A procedure to treat kidney failure in which artificial means are used to filter waste, maintain acid-base balance, and remove excess fluid from the body.
DIAPER RASH
A common condition in babies in which the skin in the diaper area becomes irritated and red, usually because of exposure to urine, feces, or heat.
DIAPHRAGM
The large, dome-shaped muscle separating the abdomen and chest that contracts and relaxes to make breathing possible; also, a thin, rubber dome that is used as a method of female contraception.
DIASTOLIC PRESSURE
The blood pressure measured when the heart is at rest between beats.
DIPHTHERIA
A bacterial infection that causes a fever, headache, sore throat, and possibly death; diphtheria is rare in developed countries.
DISTENTION
Swelling, enlargement, or stretching.
DIURETIC
A drug that increases the amount of water in the urine, removing excess water from the body; used in treating high blood pressure and fluid retention.
DNA
Deoxyribonucleic acid; responsible for passing genetic information in nearly all organisms.
DUODENAL ULCER
An erosion in the inner lining of the wall of the first part of the small intestine (called the duodenum).
DUODENUM
The first part of the small intestine, immediately following the stomach.
DYSENTERY
A severe intestinal infection, causing abdominal pain and diarrhea with blood or mucus.
DYSPNEA
Difficulty breathing.
E
ECG
An electrocardiogram, which is a record of the electrical impulses that trigger the heartbeat; used to diagnose heart disorders.
ECHOCARDIOGRAM
An image of the heart that is created by high-frequency (ultrasound) sound waves.
ECLAMPSIA
A serious condition that occurs in late pregnancy, characterized by seizures in the woman.
ECTOPIC
Occurring at an abnormal position or time.
EEG
Electroencephalography.
EMBOLISM
The blockage of a blood vessel by an embolus - something previously circulating in the blood (such as a blood clot, gas bubble, tissue, bacteria, bone marrow, cholesterol, fat, etc.).
EMPHYSEMA
A chronic disease in which the small air sacs in the lungs (the alveoli) become damaged; characterized by difficulty breathing.
ENCEPHALITIS
Inflammation of the brain, usually caused by a virus; may be very mild and barely noticeable but is usually serious and can progress from headache and fever to hallucinations, paralysis, and sometimes coma.
ENDEMIC
Describes a disease that is always present in a certain population of people.
ENDOCARDITIS
Inflammation of the inner lining of the heart, usually the heart valves; typically caused by an infection.
ENDOSCOPE
A lighted instrument used to view the inside of a body cavity.
ENZYME
A chemical, originating in a cell, that regulates reactions in the body.
ERYTHROCYTE
A red blood cell.
Esophageal spasm
Irregular contractions of the muscles in the esophagus, which lead to difficulty swallowing.
ESTROGEN
A group of hormones (produced mainly in the ovaries) that are necessary for female sexual development and reproductive functioning.
EXCISION
The surgical removal of diseased tissue.
F
FACIAL PALSY
Inability to move the muscles of the face, usually on only one side, due to inflammation of a nerve.
FEMORAL ARTERY
The main artery that supplies blood to the leg.
FEMUR
The bone located between the hip and the knee; the thighbone. with hormones.
FERTILIZATION
The joining of an egg and a sperm, creating the first cell of a new life.
FETAL DISTRESS
Physical distress experienced by a fetus because of lack of oxygen.
FETAL MONITORING
The use of an instrument to record or listen to a fetus' heartbeat during pregnancy and labor.
FETUS
The term used to refer to an unborn child from 8 weeks after fertilization to birth.
FISTULA
An abnormal passageway from one organ to another or from an organ to the body surface.
FOLIC ACID
A vitamin essential to the production of red blood cells; plays an important role in the growth a developing fetus.
FSH
See Follicle stimulating hormone.
FOLLICLE STIMULATING HORMONE
A hormone produced by the pituitary gland in the brain that stimulates the testicles to produce sperm in males and causes eggs to mature in females.
G
GASTRIC LAVAGE
Washing out of the stomach with water, often to treat poisoning; commonly called "stomach pumping".
GASTRIC ULCER
A peptic ulcer.
GASTRIN
A hormone that stimulates the release of gastric acid in the stomach.
GASTRITIS
Inflammation of the mucous membrane lining of the stomach; can have a number of causes, including viruses, bacteria, and use of alcohol and other drugs.
GASTROSCOPY
Examination of the esophagus, stomach, and the first part of the small intestine (duodenum) using an endoscope inserted through the mouth.
GENERAL ANESTHESIA
A method of preventing pain in which the patient is induced to lose consciousness.
GENERIC DRUG
A drug marketed under its chemical name, instead of a brand name.
H
HAIR FOLLICLE
A tiny opening in the skin from which a hair grows.
HDL
High-density lipoprotein.
HEART RATE
The rate at which the heart pumps blood, measured in the number of heart beats per minute.
HEART VALVE
The structure at each exit of the four chambers of the heart that allows blood to exit but not to flow back in.
HEMATEMESIS
Vomiting of blood.
HEMARTHROSIS
Bleeding into and swelling of a joint.
HEMODIALYSIS
A method used to treat kidney failure, in which blood is passed through a machine that purifies it and returns it to the body.
HEMOGLOBIN
The pigment in red blood cells that is responsible for carrying oxygen; hemoglobin bound to oxygen gives blood its red color.
HEMOGLOBINURIA
Hemoglobin in the urine.
HEMOLYSIS
the breakdown of red blood cells in the spleen, which is normal but can cause jaundice and anemia when the red blood cells are broken down too quickly.
HEPATECTOMY
Surgical removal of all or part of the liver.
HEPATITIS
Inflammation of the liver, which may be caused by a viral infection, poisons, or the use of alcohol or other drugs.
HISTAMINE
A chemical in some cells of the body that is released during allergic reactions, causing inflammation; also causes production of acid in the stomach and narrowing of the airways.
H1
Blocker- a drug that blocks the action of histamine; used to treat inflammation.
H2
Blocker- a drug used in the treatment of peptic ulcers that blocks histamine from causing acid production in the stomach.
I
IDIOPATHIC
A term used to describe something that occurs of an unknown cause.
IMMUNE DEFICIENCY
Impairment of the immune system, which reduces protection against infection and illness.
IMMUNE SYSTEM
The cells, substances, and structures in the body that protect against infection and illness.
IMPACTED FRACTURE
A bone break in which the two broken ends have been forced into each other.
Infarction
Tissue death due to lack of blood supply.
INFECTION
Disease-causing microorganisms that enter the body, multiply, and damage cells or release toxins.
INFERTILITY
The inability to have children as a result of sexual intercourse.
INFLUENZA
A viral infection characterized by headaches, muscle aches, fever, weakness, and cough; commonly called the "flu".
GLUCOSE
(the body's main source of energy) into muscle cells.
INTESTINE
A long, tube-shaped organ that extends from the stomach to the anus; absorbs food and water and passes the waste products of digestion as feces.
INTRAVENOUS
Inside of or into a vein.
IQ
Intelligence quotient; a measure of a person's intelligence as determined by specific tests.
J
JAUNDICE
Yellowing of the skin and whites of the eyes because of the presence of excess bilirubin in the blood; usually a sign of a disorder of the liver.
K
KERATIN
A tough protein found in skin, nails, and hair.
KIDNEY
One of two organs that are part of the urinary tract; responsible for filtering the blood and removing waste products and excess water as urine.
KIDNEY STONE
A hard mass composed of substances from the urine that form in the kidneys.
KILLER T CELLS
White blood cells that are part of the immune system and destroy microorganisms and cancer cells.
L
LABIA
The two pairs of skinfolds that protect the opening of the vagina.
LABOR
The interval from onset of contractions to birth of a baby.
LACTATION
The production of breast milk after giving birth.
LACTOSE
The sugar found in dairy products.
LARYNGECTOMY
Surgical removal of all or part of the voice box (larynx) as a treatment for cancer.
LARYNGITIS
Inflammation of the voice box, usually caused by a viral infection; characterized by a hoarse voice.
LARYNX
The medical term for the voice box, the organ in the throat that produces voice and also prevents food from entering the airway.
LDL
See Low-density lipoprotein.
LEUKOCYTE
Another name for a white blood cell.
LEUKOCYTE COUNT
The number of white blood cells in the blood, which is used as a measure of health and possible infection.
LIPOMA
A noncancerous tumor of fatty tissue.
LIPOPROTEINS
Substances containing lipids and proteins, comprising most fats in the blood.
LIVER
The largest organ in the body, producing many essential chemicals and regulating the levels of most vital substances in the blood.
M
MAGNESIUM
A mineral that is essential for many body functions, including nerve impulse transmission, formation of bones and teeth, and muscle contraction.
MALFORMATION
Abnormal development of an organ or tissue.
MAMMOGRAPHY
An X-ray procedure done to detect breast cancer.
MASTECTOMY
A surgical procedure in which all or part of the breast is removed to prevent the spread of cancer.
MASTITIS
Inflammation of the breast, which is usually caused by a bacterial infection.
MELANOCYTES
Cells that produce the pigment melanin.
MENORRHAGIA
Excessive loss of blood during menstruation, which can be caused by disorders of the uterus.
MINERAL
A substance that is a necessary part of a healthy diet (such as potassium, calcium, sodium, phosphorus, and magnesium).
MITRAL STENOSIS
A condition in which the mitral valve in the heart becomes narrowed, making the heart work harder to pump blood; can lead to symptoms such as shortness of breath.
MITRAL VALVE
The valve in the heart that allows blood to flow from the left atrium to the left ventricle, but prevents blood from flowing back in.
MYOCARDIUM
The medical term for heart muscle.
MYOSITIS
Muscle inflammation, causing pain and weakness.
N
NAUSEA
Feeling the need to vomit.
NECROSIS
The medical term for the death of tissue cells.
NEPHRITIS
Inflammation of one or both kidneys because of an infection, an abnormal immune system response, or a disorder of metabolism.
NEPHRONS
The tiny filtering units of the kidney.
NERVE
A bundle of fibers that transmit electrical messages between the brain and areas of the body; these messages convey sensory or motor function information.
NEURON
Another term for a nerve cell.
NSAID
Nonsteroidal anti-inflammatory drug.
NUTRIENT
Any substance that the body can use to maintain its health.
O
OBESITY
A condition in which there is an excess of body fat; used to describe those who weigh at least 20 percent more than the maximum amount considered normal for their age, sex, and height.
OLFACTORY NERVES
Nerves that play a role in the sense of smell.
OLIGOSPERMIA
A low level of sperm in the semen; one of the main causes of infertility in men.
OPTIC NERVES
he pair of nerves that carry visual information from the retina to the brain.
OPTIC NEURITIS
Inflammation of the optic nerve, often causing a partial loss of vision.
ORGANISM
Any single, functioning form of life.
ORGASM
Involuntary contraction of genital muscles experienced at the peak of sexual excitement.
OSTEITIS
Inflammation of bone.
OVARIES
Two almond-shaped glands located at the opening of the fallopian tubes on both sides of the uterus; produce eggs and the sex hormones estrogen and progesterone.
OVULATION
The development and release of the egg from the ovary, which usually occurs halfway through a woman's menstrual cycle.
OVUM
Another term for an egg cell.
OXYGEN
A gas that is colorless, odorless, and tasteless; essential to almost all forms of life.
OXYTOCIN
A hormone produced in the pituitary gland that causes contraction of the uterus during childbirth and stimulation of milk flow during breast-feeding.
P
PACEMAKER
A small electronic device that is surgically implanted to stimulate the heart muscle to provide a normal heartbeat.
PANCREATITIS
Inflammation of the pancreas, which is often caused by alcohol abuse.
PANDEMIC
A widespread epidemic.
PATHOGENESIS
the production and development of a disease or disorder.
PATHOGEN
any substance capable of causing a disease; usually refers to a disease-causing microorganism.
PELVIC EXAMINATION
An examination of a woman's reproductive organs.
PENIS
The external male reproductive organ, which passes urine and semen out of the body.
PEPTIC ULCER
An erosion in the lining of the esophagus, stomach, or small intestine, usually caused in part by the corrosive action of gastric acid
PID
See Pelvic inflammatory disease.
PITUITARY GLAND
A small, round gland located at the base of the brain that releases hormones that control other glands and body processes.
PLACENTA
An organ formed in the uterus during pregnancy that links the blood of the mother to the blood of the fetus; provides the fetus with nutrients and removes waste.
PNEUMONIA
Inflammation of the lungs due to a bacterial or viral infection, which causes fever, shortness of breath, and the coughing up of phlegm.
POLYCYTHEMIA
An increased amount of red blood cells in the blood.
POLYURIA
The excessive production of urine; can be a symptom of various diseases, most notably diabetes mellitus.
PORTAL VEIN
The vein connecting the stomach, intestines, and spleen to the liver.
POSTERIOR
describes something that is located in or relates to the back of the body.
POSTMENOPAUSAL BLEEDING
Bleeding from the vagina that occurs after menopause.
POSTMORTEM EXAMINATION
Examination of a body after death to determine the cause of death; commonly called an autopsy.
POSTNATAL
Describes something that occurs after birth, usually to the baby.
Q
QUADRICEPS MUSCLE
The muscle (consisting of 4 distinct parts) located at the front of the thigh that straightens the leg.
R
RABIES
An infectious viral disease primarily affecting animals; can be transmitted to humans through an infected animal's bite; if untreated, can result in paralysis and death.
RADIOGRAPHY
The formation of images of the inside of the body using radiation projected through the body and onto film; a radiograph is also called an X-ray.
RED BLOOD CELL
A doughnut-shaped blood cell that carries oxygen from the lungs to body tissues.
REHYDRATION
Treatment for dehydration (an abnormally low level of water in the body) in which levels are restored by taking fluids containing water, salt, and glucose by mouth or, if severe, through a vein.
RESPIRATORY SYSTEM
The organs that carry out the process of respiration.
RHEUMATOID ARTHRITIS
A condition in which joints in the body become inflamed, stiff, painful, and sometimes deformed because of the body's own immune system attacking the tissues.
RHINITIS
Inflammation of the mucous membrane lining the nose, which can cause sneezing, runny nose, congestion, and pain; when caused by substances in the air, it is called allergic rhinitis or hay fever.
RNA
Ribonucleic acid, which helps to decode and process the information contained in DNA.
S
SACRUM
The triangular bone located at the bottom of the spine that is connected to the tailbone, the hipbones near the sacroiliac joints, and the rest of the spine.
SARCOMA
A cancer in connective tissue, fibrous tissue, or blood vessels.
SCABIES
A highly contagious skin disorder caused by a mite that burrows into the skin and produces an intense, itchy rash.
SCLERA
The tough, white coating that covers and protects the inner structures of the eye.
SCROTUM
The sac containing the testicles.
SEMINAL VESICLES
Two saclike glands in men that produce part of the fluid in semen.
SEPSIS
The infection of a wound or tissue with bacteria, causing the spread of the bacteria into the bloodstream; now also known as systemic inflammatory response syndrome caused by a microbe.
SPERM
The male sex cell produced in the testicles.
SPERM ANTIBODY
An antibody against sperm that can be produced by a woman’s immune system.
SPHINCTER
A ring of muscle fibers located around a naturally occurring passage or opening in the body that opens and closes to regulate passage of substances.
SPHYGMOMANOMETER
An instrument used to measure blood pressure.
SPINAL CORD
A long tube of nerve tissue inside the spinal column, running from the brain down the length of the back inside of the spine.
SPLEEN
An organ located in the upper left abdomen behind the ribs that removes and destroys old red blood cells and helps fight infection.
SPLENECTOMY
Surgical removal of the spleen.
STD
Sexually transmitted disease.
STEM CELLS
Cells that give rise to the different types of blood cells.
STENOSIS
Narrowing of a body passageway.
STERNUM
The long, flat bone located at the center of the chest.
STOOL
Another term for feces.
STRESS FRACTURE
A bone break resulting from repeated pressure on the bone.
STROKE
Damage to part of the brain because of a lack of blood supply (due to a blockage in an artery) or the rupturing of a blood vessel; leads to complete or partial loss of function in the area of the body that is controlled by the damaged part of the brain.
SUTURE
A surgical stitch that helps close an incision or wound so that it can heal properly.
SWEAT GLANDS
Tiny structures in the skin that secrete sweat.
SYNDROME
A group of symptoms that indicate a certain disorder when they occur together.
SYPHILIS
A sexually transmitted disease; initially causes only painless sores on the genitals but can be life-threatening if untreated.
SYSTEMIC
Affecting the whole body.
SYSTOLIC PRESSURE
The blood pressure measured while the heart is contracting.
T
TACHYCARDIA
A rapid heart rate (over 100 beats per minute).
TEAR DUCT
A tiny passageway that drains lubricating tears from the surface of the eye to the back of the nose.
TENDON
Strong connective tissue cords that attach muscle to bone or muscle to muscle.
TENDINITIS
Inflammation of a tendon, usually caused by injury, characterized by pain, tenderness, and sometimes limited movement in the attached muscle.
TESTICLES
The two male sex organs that produce sperm and the sex hormone testosterone.
TETANUS
A sometimes fatal disease affecting the brain and spinal cord; caused by infection with bacterium present in soil and manure.
THROMBECTOMY
Removal of a blood clot.
THROMBOSIS
A condition in which a blood clot (thrombus) has formed inside a blood vessel.
THROMBUS
A blood clot in a blood vessel.
Toxin
A poisonous substance. Fever, headache, abdominal discomfort, and enlargement of the liver and spleen.
U
ULCER
An open sore that occurs on the skin or on a mucous membrane because of the destruction of surface tissue.
ULCERATIVE COLITIS
A chronic condition in which ulcers occur on the mucous membrane lining of the colon (the end of the large intestine) and the rectum.
UMBILICAL CORD
The tubal structure (consisting of two arteries and one vein) that connects the fetus to the placenta, supplying the fetus with oxygen and nutrients and removing some waste products.
UMBILICAL HERNIA
A condition present at birth in which a part of the baby's intestines bulge through a weak area of the abdominal wall, creating a swelling around the navel.
UNCONSCIOUSNESS
A temporary or prolonged loss of awareness of self and of surroundings.
UREA
A waste product of the metabolism of proteins that is formed by the liver and secreted by the kidneys.
URETERS
Two tubes that carry urine from the kidneys to the bladder.
URETHRA
The tube by which urine is released from the bladder.
URETHRITIS
Inflammation of the urethra.
URINARY TRACT
The structures in the body that are responsible for the production and release of urine, including the kidneys, ureters, bladder, and urethra.
V
VAGINA
The muscular passage connecting the uterus with the outside genitals; a component of the female reproductive system.
VAGINITIS
Inflammation of the vagina, which can be the result of infection, aging, a hormone deficiency, or a foreign object (such as a tampon).
VALVE
A structure that allows fluid flow in only one direction.
VARIOLA
Another term for smallpox.
VASCULAR
Pertaining to blood vessels.
VASCULITIS
Inflammation of blood vessels.
VAS DEFERENS
A thin tube that stores and transports sperm.
VEIN
A blood vessel that carries blood toward the heart.
VERTIGO
The feeling that one or one's surroundings are spinning.
VIRUS
The smallest known disease-causing microorganism; viruses are very simple in structure and can only multiply when they are inside the cell of another organism.
VITAMIN A
A vitamin essential for normal growth and development of the body (most notably the bones and teeth), protection of mucous membranes from infection, normal vision, and healthy skin and hair.
VITAMIN B COMPLEX
A group of vitamins including thiamine, niacin, riboflavin, pantothenic acid, pyridoxine, biotin, and folic acid; plays a variety of important roles in the body, including in hormone production, metabolism, and functioning of the nerves, muscle, heart, and digestive system.
VITAMIN B6
A vitamin that plays an important role in the breakdown and use of energy sources, production of red blood cells and antibodies, and normal functioning of the nervous system.
VITAMIN B12
A vitamin that is essential to the production of DNA (the genetic material in cells) and red blood cells and in the functioning of the nervous system.
VITAMIN C
A vitamin with many essential roles, including in maintaining healthy bones, teeth, gums, ligaments, and blood vessels and in the immune system's response to infection
VITAMIN D
A vitamin that plays a role in the absorption of calcium by the intestines and is essential for healthy bones and teeth.
Vitamin E
A vitamin that protects tissues from damage by oxygen free radicals, helps to form red blood cells, maintains the function of enzymes, and maintains cell structure.
VITAMIN K
A vitamin that is essential for normal blood clotting and the body's absorption of calcium.
VITAMINS
Complex substances that are necessary in small amounts to maintain health and ensure proper development and functioning of the body.
W
WHEEZE
A high-pitched sound produced during breathing because of narrowing of the airways; common sign of asthma.
WHITE BLOOD CELL
A group of colorless blood cells that are part of the immune system, helping prevent and fight infection.
WITHDRAWAL BLEEDING
Bleeding from the vagina that occurs when hormone levels drop, such as menstruation or the bleeding that occurs at the end of each cycle of the combined oral contraceptive pill.
X
X CHROMOSOME
One of the two sex chromosomes; determines female sex characteristics.
X-RAY
RADIOGRAPHY.
XYY SYNDROME
A disorder in which a man has an extra Y chromosome, causing him to be unusually tall and to have behavioral disorders.
Y
Y CHROMOSOME
One of the two sex chromosomes; determines male sex characteristics.
YEAST INFECTION
A term usually referring to a candidiasis infection.
YELLOW FEVER
A life-threatening viral infection transmitted by mosquitoes that causes jaundice, fever, headache, and vomiting.
Z
ZINC CHLORIDE
A white powder used as an antiseptic and antiperspirant.
ZOONOSIS
A parasite-caused or infectious disease in animals that can be transferred to humans.
ZYGOTE
The cell that results when an egg is fertilized by a sperm.