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The Complete Idiot's Guide to a Smart Vocabulary The Complete Idiot's Guide to a Smart Vocabulary

What's Up, Doc? Understanding Medical Terminology

In This Chapter

"Words are the physicians of a mind diseased."
—Aeschylus, Greek playwright

Medical students spend many years memorizing and learning how to pronounce tongue-twisting terms such as "otorhinolaryngology" and "cholecystogastronomy" and head-scratching phrases such as "ureteroscopic ultrasonic lithotripsy" and "percutaneous transluminal coronary angioplasty." Ow! Unfortunately, having mastered these brain-benders, words with only three or four syllables such as arrhythmia and diuretic come to seem simplistic and obvious. This means, of course, that it's those words we're subjected to as patients. To help you understand just what in the name of Hippocrates your doctor is jabbering on about, this chapter explains some common medical terminology including general words for diseases, useful medical prefixes and suffixes, and words related to symptoms, diagnosis, and treatment.

If you're hankering for more, the book has a section titled "Medicine Men and Women," in Chapter 12, "Words at Work: Job Titles and Professions."

An Easy Start: Some General Disease Terms

The word disease (di·ZEEZ) combines dis-, "absence of," with ease, "comfort," and it originally meant pretty much what you'd think: "discomfort; uneasiness." Because physical problems caused such discomfort and uneasiness, the word disease eventually came to mean "a condition that impairs the healthy functioning of an organism." A synonym is malady (MAL·uh·dee). If the disease is accompanied by pain and suffering, you can call it an affliction (uh·FLIK·shun). If the disease is mild, call it a disorder (dis·OR·dur) or an ailment (AYL·munt).

A pathogen (PATH·uh·jun, noun) is a microorganism (such as a bacterium) or other agent that causes disease. If it causes cancer, in particular, it's a carcinogen (kar·SIN·uh·jun).

Acute (uh·KYOOT, adj.) describes a disease that has a rapid onset, severe symptoms, and a relatively short duration. The opposite is chronic (KRON·ik, adj.), which describes a disease that has a gradual onset and lasts a long time with frequently recurring symptoms.

If a disease is contagious (kun·TAY·jus, adj.), it's readily transmittable ("able to be passed from one organism to another") by direct or indirect contact. You can also say that the disease is communicable (kuh·MYOO·ni·kuh·bul, adj.) or infectious (in·FEK·shus, adj.), although the latter especially applies to diseases caused by microorganisms such as bacteria or viruses. If the disease is extremely infectious (or extremely malignant), describe it as virulent (VEER·yuh·lunt, adj).

See also: congenital.

An exceptionally contagious disease might end up as an epidemic (ep·uh·DEM·ik, noun), an outbreak of a disease that spreads more quickly and to more people than would normally be expected. If everyone in a particular geographic area is infected with the disease, it becomes a pandemic (pan·DEM·ik, noun). If a disease is common is a particular area, it's said to be endemic (en·DEM·ik, adj.).

The word malignant (muh·LIG·nunt, adj.) describes a tumor or symptom that's life threatening, especially one that spreads rapidly through the body. If this spreading involves a tumor or other cancerous growth, the process is called metastasis (muh·TAS·tuh·sis, noun), and the tumor is said to metastasize (muh·TAS·tuh·size, verb). If a tumor or other symptom poses no danger to a person's health now or in the future, it's described as benign (bi·NINE, adj.).

To relapse (ri·LAPS, verb) is to experience the symptoms of a disease again, or in a more intense manner, after having apparently recovered. The recurrence of the disease is also called a relapse (REE·laps, noun). The opposite is for the disease to go into remission (ree·MISH·un, noun), which means the symptoms either become less intense or disappear altogether.

Word Anatomy: Some Medical Prefixes and Suffixes

The key to understanding many different medical terms is to become familiar with a few key prefixes and suffixes. This is what you'll do here in this section.

The following table presents no less than 32 prefixes related to parts of the human body. Note that, in all cases, the "o" is dropped in words in which the suffix begins with a vowel. For example, cardiology (-logy suffix, "the study of") and cardiac (-ac suffix, "pertaining to").

Prefix Refers To Prefix Refers To
immuno-immune systemlaryngo-larynx

The following table presents a general list of medical suffixes.
Suffix What It Means Suffix What It Means
-dermskin-ectomysurgical removal of
-emiablood condition-genesisorigin
-geniccausing-gramtracing; record
-iasisdiseased condition-iatrichealing practice
-opiaeye defect-osisdiseased condition
-ostomysurgical opening-otomysurgical incision
-pathydiseased condition-plastysurgical reconstruction
-plegiaparalysis-scopyvisual exam

Sign, Sign, Everywhere a Sign: Words for Symptoms

A symptom (SIMP·tum, noun) is a characteristic sign or indication of a disease. A group of symptoms that characterize a disease is called a syndrome (SIN·drome or SIN·drum, noun). If a symptom appears that isn't related to the disease, it's called an epiphenomenon (ep·uh·fi·NOM·un·non, noun). If a person doesn't display the symptoms of a disease, describe that person as asymptomatic (ay·simp·tuh·MAT·ik, adj.).

If a person complains of having the symptoms of a disease, but those symptoms are not physically present, she's a hypochondriac.

The rest of this section runs through words for some common symptoms.

Angina (an·JYE·nuh, noun) is a severe and suffocating chest pain caused by a lack of blood flow through the heart.

Arrhythmia (uh·RITH·mee·uh, "th" as in "the," noun) is an irregularity in the rhythm or strength of the heart beat. See also palpitation.

Atrophy (AT·truh·fee, noun) is the wasting away or shrinking of a bodily part, organ, or tissue due to a disease (or possibly an injury or idleness). This word combines a-, "without," and -trophy, "growth." The opposite is hypertrophy (hye·PUR·truh·fee, noun), the nontumorous increase in size of a part, organ, or tissue (hyper- means "excessive").

Dyspepsia (dis·PEP·see·uh, noun) is a fancy term for indigestion (in·duh·JES·chun, noun), the inability to digest or difficulty in digesting food, causing stomach discomfort and gas.

Enervation (EN·ur·vay·shun, noun) is a condition of weakness and lack of energy. A synonym is debilitation (duh·BIL·uh·tay·shun, noun).

A fever (FEE·vur, noun) is a body temperature above the normal 98.6 degrees. It's also called pyrexia (pye·REK·see·uh, noun) or hyperthermia (hype·pur·THUR·mee·uh, noun). See also hypothermia.

A heart murmur is a blowing or fluttering sound in the chest caused by turbulent blood flow through a defective heart valve.

A hemorrhage (HEM·ur·ij, noun) is an excessive loss of blood due to a ruptured blood vessel (a tubular channel through which blood flows; an artery, vein, or capillary). This is also called internal bleeding.

Hypoglycemia (hye·poh·glye·SEE·mee·uh, noun) is an abnormally low level of sugar in the blood. Having too much blood sugar is called hyperglycemia.

Hypertension (hye·pur·TEN·shun, noun) is abnormally high blood pressure, the pressure exerted by the blood against the walls of the arteries. When you get your blood pressure taken, what do the numbers mean? To find out, first you need to know that the heart pumps in a two-stage process. The systole (SIS·tuh·lee, noun) is the contraction of the heart, during which blood is pumped out of the heart and into the arteries, and the diastole (dye·AS·tuh·lee, noun) is the expansion of the heart, during which it fills with blood from the veins. Blood pressure tells you the systolic pressure (the pressure against the arteries when blood is pumped out of the heart) over the diastolic pressure (the pressure against the arteries when the heart is filling up with blood).

Hyperventilation (hye·pur·ven·tuh·LAY·shun, noun) is an abnormally rapid or deep breathing that leads to reduced carbon dioxide in the blood. It raises blood pressure and can cause fainting.

Hypothermia (hype·po·THUR·mee·uh, noun) is an abnormally low body temperature. See also hyperthermia.

Inflammation (in·fluh·MAY·shun, noun) is a defensive reaction exhibited by tissue that is injured, irritated, or infected. It's characterized by swelling, redness, pain, and heat.

A lesion (LEE·zhun, noun) is an injury to tissue that results in an abnormal structural change of the affected organ or body part. A tumor is an example of a lesion, as is an abscess (AB·ses, noun)—an accumulation of pus surrounded by inflamed tissue—or an ulcer (UL·sur, noun)—an open and inflamed sore on the skin or on a mucous membrane (such as the stomach lining or the duodenum, the first part of the small intestine).

Neuralgia (noo·RAL·ja or nyoo·RAL·ja, noun) is a sharp paroxysmal pain radiating along one or more nerves.

A palpitation (pal·puh·TAY·shun, noun) is an abnormally rapid or violent heartbeat. A rapid heartbeat is also called tachycardia (tak·i·KAR·dee·uh, noun). See also arrhythmia.

A paroxysm (PAIR·uk·siz·um, noun) is an abrupt, violent spasm or convulsion. It can also refer to a sudden recurrence or worsening of symptoms. (In the nonmedical world, you can use paroxysm to refer to any sudden outburst of emotion or action; for example, "a paroxysm of grief.")

"Give It to Me Straight, Doc": Diagnosis Terms

Diagnosis (dye·ug·NO·sis, noun) is the identification of a disease based on the patient's medical history and the results of a physical examination and laboratory tests. The cause or origin of a disease as determined by a diagnosis is called the etiology (et·ee·OL·uh·gee, noun).

Let's look at some diagnostic words:

Auscultation (aw·skul·TAY·shun) is the technique of listening to the body's internal organs, especially the heart, lungs, and abdominal organs, usually with a stethoscope.

A biopsy (BYE·op·see, noun) is the removal of a small sample of tissue for examination in a laboratory.

A CAT scan (noun) is series of x-ray scans of a body part; it produces a cross-sectional or three-dimensional view of that part. This is useful for detecting tumors or other anomalies. CAT stands for computerized axial tomography.

An EEG (ee·ee·gee, noun) is an electroencephalograph (i·LEK·troh·en·SEF·uh·luh·graf), a machine that detects and records the electrical activity of the brain via small electrodes attached to the scalp. The graphical record of the brain activity is called an electroencephalogram (i·LEK·troh·en·SEF·uh·luh·gram; also abbreviated as EEG). Since this graph usually appears as a series of wavy lines, the brain's electrical activities are called brain waves.

An EKG (ee·kay·gee, noun) is an electrocardiograph (i·LEK·troh·KAR·dee·oh·graf), a machine that detects and records the electrical activity of the heart muscle using electrodes attached to the chest. The graphical tracings of the heart muscle activity result in an electrocardiogram (i·LEK·troh·KAR·dee·oh·gram; also abbreviated as EKG). Note that the expected abbreviation—ECG—is also used, although not as frequently. To keep us all confused, ECG is sometimes used as a short form of echocardiograph (EK·oh·KAR·dee·oh·graf), a machine that uses sound waves to visualize the structure and workings of the heart.

Endoscopy (en·DAWS·kuh·pee, noun) is the insertion of an endoscope through a small incision to examine the inside of some portion of the body. An endoscope (EN·duh·skope, noun) is a long, thin, lighted tube that uses fiber optics to enable the doctor to view inside a body cavity. Here are some common endoscopy procedures:

arthroscopy (ar·THRAWS·kuh·pee, "th" as in "thin." noun)—Examines the inside of a joint

bronchoscopy (brawn·KAWS·kuh·pee, noun)—Examines the bronchi (BRONG·kee, noun; the two man branches of the trachea that lead to the lungs)

colonoscopy (ko·luh·NAWS·kuh·pee, noun)—Examines the inside of the colon

gastroscopy (ga·STRAWS·kuh·pee, noun)—Examines the inside of the stomach

Exploratory (ek·sploh·RUH·tor·ee) surgery is a surgical procedure designed only to examine the patient internally to help further a diagnosis.

Mammography (ma·MOG·ruh·fee, noun) is the x-ray examination of the breasts. The resulting mammogram (MAM·uh·gram, noun) enables the doctor to look for tumors.

MRI (em·ar·eye, noun) stands for magnetic resonance imaging, a technique that uses an electromagnetic field to create images of the body's soft tissues.

A Pap smear (noun) is a test, especially of the female genital tract, for cancer that takes a tissue sample (a "smear") and treats it with a special stain that shows possible problems when examined under a microscope. This test is named after George Papanicolaou, the doctor who discovered it. This is also called a Pap test.

A PET scan (noun) is an x-ray scan of the body that generates detailed images of body tissue by detecting emissions from injected radioactive molecules. This technique is useful for detecting certain cancers and brain tumors. PET is short for positron emission tomography.

Just What the Doctor Ordered: Treatment Terms

This section looks at a few words and phrases related to the treatments, medications, and remedies that doctors give to their patients. To prescribe (pruh·SCRIBE, verb) means to order a patient to follow a course of treatment, especially to take a specific drug (or drugs) at set times and dosages and for a specified length of time. The drug (or drugs) so prescribed is a prescription (pruh·SKRIP·shun, noun). Prescribe comes from the Latin word praescribere, which means "to write before."

Speaking generally, if the treatment serves only to lessen the symptoms without curing the disease, call it a (or describe it as) palliative (PAL·ee·ay·tiv). Also, a panacea (pan·uh·SEE·uh, noun) is a mythical remedy that cures all diseases. It's also called a cure-all or a catholicon (kuh·THOL·i·kon, "th" as in "thin"). A nostrum (NOS·trum, noun) is a favorite remedy that has never been proven to be effective. This word is now more often applied to political, social, or economic problems.

An analgesic (an·ul·GEE·zik, noun) is a medication that reduces or eliminates pain without the patient losing consciousness. Also called a painkiller or an anodyne (AN·uh·dine). (The latter is also an adjective that's often used more generally to mean "soothing; relaxing.") Pain-relieving substances include aceteminophen (uh·SEE·tuh·MIN·uh·fuhn), aspirin (AS·prin or AS·puh·rin), codeine (KOH·deen), ibuprofen (eye·byoo·PRO·fuhn), and morphine (MOR·feen).

An antibiotic (an·tee·bye·AWT·ik, noun) is a medicine that can kill or inhibit the growth of microorganisms that cause bacterial infections. Examples are penicillin (pen·uh·SIL·un, noun) and streptomycin (strep·tuh·MY·sun, noun).

An antiemetic (an·tee·uh·MET·ik, noun) is a drug that prevents vomiting.

An antihistamine (an·tee·HIS·tuh·meen or an·tee·HIS·tuh·min, noun) is a drug that treats the symptoms produced during an allergy attack. The drug blocks the physiological effects of histamine (HIS·tuh·meen, noun), a compound that's released during an allergic reaction and that causes sneezing, itchiness, a runny nose, and other symptoms.

A diuretic (dye·uh·RET·ik, noun) is a medication that eliminates excess water by increasing the body's urine output.

A laxative (LAK·suh·tiv, noun) is a food or drug that stimulates bowel movements. It's also called a cathartic (kuh·THAR·tik), a physic (FIZ·ik), or a purgative (PUR·guh·tiv).

A sedative (SED·uh·tiv, noun) is a drug that depresses the central nervous system to create a calming effect or to induce sleep. It's also known as a barbiturate (bar·BICH·ur·it), a calmative (KAH·muh·tiv or KAHL·muh·tiv), a depressant (duh·PRES·unt), or a tranquilizer (TRANG·kwuhl·eye·zur). A drug that causes sleep is also called a soporific (sop·uh·RIF·ik) or a hypnotic (hip·NOT·ik).

Finally, a placebo (pluh·SEE·boh, noun) is a substance or treatment with no medicinal qualities but that's presented to the patient as real medicine, which often causes the patient's condition to improve. An improvement in a patient's condition that arises only from the patient's belief that a treatment will cause such improvement is called the placebo effect. The opposite is a nocebo (noh·SEE·boh, noun), a nonmedicinal substance that causes harmful effects because the person taking the substance expects those effects.

Questions and Exercises to Help Everything Sink In

Here's a list of the main words you learned in this chapter:











CAT scan











exploratory surgery


heart murmur
















Pap smear



PET scan








In the following questions, hover your mouse pointer over the word Answer to see the answer in your browser's status bar:

  1. Fill in the blank: "Neuralgia consists of sharp ______ of pain radiating along one or more nerves." Answer

  2. Choose the word that means "the removal of a small sample of tissue for examination": Answer

    a. biopsy
    b. endoscopy
    c. auscultation
    d. lesion

  3. Fill in the blank: "As a dedicated ______, Gaston could always be counted on to think he'd fallen victim to whatever disease was going around." Answer

Match the word on the left with the short definition on the right:

  1. palliative Answer a. life-threatening
  2. pathogen Answer b. irregular heart beat
  3. malignant Answer c. abnormally rapid heart beat
  4. arrhythmia Answer d. disease-causing microorganism
  5. palpitation Answer e. treatment that lessens symptoms

  6. Fill in the blanks: "The ______ carry blood away from the heart and the ______ carry blood to the heart." Answer

  7. Choose the word that's an antonym for acute: Answer

    a. endemic
    b. cathartic
    c. soporific
    d. chronic

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