Introduction to Medical

Terminology

Chapter 1

WORD PARTS ARE THE KEY!!

• Learning medical terminology is much easier once you understand how word parts work together to form medical terms.

Three Types of Word Parts:• Word roots:• Contain the basic meaning of the

term. They usually, but not always, indicate the body part.

• Examples: oste/o, neur/o• They act as the foundation of

most medical terms.

• Suffixes:• Usually, but not always,

indicate the procedure, condition, disorder, or disease. A suffix always comes at the end of the word.

• Prefixes:• Usually, but not always,

indicate location, time, number or status.

• A prefix always comes at the beginning of a word.

So….Word Part Guidelines:• A word root cannot stand alone.

A suffix must be added to complete the term.

• The rules for use of combining vowels apply when a suffix is added to a word root.

• When a prefix is needed, it is always placed at the beginning.

Combining Vowels• A combining vowel may be

needed between the word root and the suffix to make the medical term easier to pronounce.

• The letter “o” is the most commonly used combining vowel.

• When a word root is shown with a back slash and a combining vowel, such as cardi/o, this format is referred to as the combining form.

• So…the word root + the combining vowel = combining form.

Rules for Using Combining Vowels:

• A combining vowel is used when the suffix begins with a consonant.

• Example: when neur/o is joined with the suffix –plasty, the combining vowel is used due to the consonant. “Neur/o/plasty”

• A combining vowel is not used when the suffix begins with a vowel (a,e,i,o,u).

• Example: when neur/o is combined with the suffix –itis, the combining vowel is not used, because the suffix “–itis” begins with a vowel.

• Word: neur/itis

• A combining vowel is always used when two or more word roots are joined.

• Example: When gastr/o is joined with enter/o, the combining vowel is used. “gastr/o/enter/o

• But if you add a suffix that starts with a vowel, you will not use it:

• Word: gastr/o/enter/itis

• A prefix does not require a combining vowel.

• The prefix is attached directly onto the word root.

Word Roots Indicating Color• cyan/o• = “blue”• Example:• cyan/osis = a blue discoloration

of the skin caused by a lack of adequate oxygen

• cyan + -osis (condition of)

• erythr/o• = “red”• Example:• erythro/cytes = red blood cells.

Erythr = red + “o” for the combining vowel + cytes (cells).

• leuk/o• = “white”• Example:• leukocytes = leuk (white) + “o”

for the combining vowel + cytes (cells).

• melan/o• = “black”• Example:• melanoma = melan/o + the

suffix “-oma” (tumor)• Note: the combining vowel was

dropped since the suffix begins with a vowel.

• poli/o• = “gray”• Example:• Poli/o/myel/itis – an inflammation of

the gray matter of the spinal cord usually causing paralysis.

• Note: the combining vowel was used to connect the word roots but dropped from myel/o to join it with –itis.

Let’s talk about suffixes….• Suffixes usually, but not always,

indicate the procedure, condition, disorder or disease:

• Examples: tonsill/o = tonsils. Tonsill + -itis (inflammation) = tonsillitis

• Tonsill/o + -ectomy (surgical removal) = tonsillectomy

• Some suffixes complete the term by changing the word root into an adjective. Many of these suffixes are defined as “pertaining to”.

• Most common: -al, -ic, -ac• Examples: cardi/ac, gastr/ic,

enter/al.

• Some suffixes complete the term by changing the word root into a noun.

• Example: “-um” is a noun ending.

• Crani/um = “crani” means skull, and “-um” is a noun ending.

• Cranium is the portion of the skull that surrounds the brain.

• Some suffixes have a general meaning of “abnormal condition”.

• For example, -osis means an abnormal condition.

• “Gastrosis” means any abnormal condition of the stomach.

• Gastr/o = stomach; -osis = abnormal condition.

• Pathology means the study of disease and the suffixes related to pathology describe specific disease conditions.

• These suffixes will repeat each chapter, so you must learn them in order to build words for each body system.

• -algia means “pain”. Example: gastr/algia = stomach pain. Note: the combining vowel was not used: suffix starts with vowel

• -dynia also means “pain”. Example: gastr/o/dynia = stomach pain. Notice, the combining vowel was used since the suffix begins with a consonant.

• -itis means “inflammation”.• Example: gastr/itis means

inflammation of the stomach.• Note: the combining vowel was

dropped from gastr/o since “-itis” begins with a vowel.

• Another example we saw in a previous slide: tonsill/itis.

• -malacia means “abnormal softening.”

• Example: crani/o/malacia = abnormal softening of the skull.

• crani = skull + “o” + -malacia• Note: the combining vowel was

used because the suffix begins with a consonant.

• -megaly means “enlarged” or enlargement of.

• Example: hepat/o/megaly• hepat/o means “liver”• -megaly means “enlarged”• so….hepat/o/megaly means

“enlarged liver”.• To make it easy, remember that

“mega” means big, large.

• -necrosis means “tissue death”.

• Example: arteri/o/necrosis• means “death of tissue of an

artery”• arteri/o = artery; -necrosis =

death of tissue• Note: combining vowel was used

since the suffix begins with a consonant.

• -sclerosis means “abnormal hardening” (is the opposite of –malacia).

• Example: arteri/o/sclerosis• means “abnormal hardening of

the arteries”• Note: combining vowel was used

since the suffix begins with a consonant.

• -stenosis means “abnormal narrowing”

• Example: arteri/o/stenosis means “abnormal narrowing of the arteries”

• arteri/o = arteries; -stenosis = abnormal hardening.

• Note: combining vowel was used. Why?

• Some suffixes identify a procedure that is performed on the body part identified by the word part.

• Again, these suffixes are the building blocks for word used in each of the chapters, so learn them as quickly as possible.

• -centesis means “surgical puncture to remove fluid”.

• Example: abdomin/o/centesis• Means “a surgical puncture of

the abdominal cavity to remove fluid.”

• abdomin/o = abdomen; -centesis = surgical puncture.

• -ectomy means “surgical removal of”.

• Example: tonsill/ectomy = surgical removal of tonsils.

• append/ectomy = surgical removal of the appendix.

• The combining vowel would never be used with –ectomy since it starts with a vowel.

• -graphy means “the process of recording a picture or record.”

• Example: mamm/o/graphy = the process of taking a picture (x-ray) of the breast.

• -gram means “the picture or record itself”.

• Example: mamm/o/gram = the picture (x-ray) of the breast.

• -ostomy means “to surgically create an artificial opening”.

• Example: col/ostomy = the surgical creation of an opening between the colon and the body surface. Col/o = colon.

• To remember this suffix, think of “os” as a word that means “opening”.

• -otomy means “surgical incision, or cutting into”.

• Example: col/otomy = surgical incision into the colon.

• Splen/otomy = surgical incision into the spleen.

• Arteri/otomy = surgical incision into an artery.

• -plasty means “surgical repair”.

• Example: my/o/plasty = surgical repair of a muscle.

• my/o = muscle; -plasty = surgical repair.

• abdomin/o/plasty = surgical repair of the abdomen.

• -scopy means “visual examination of a body cavity or organ by use of a scope”

• Example: arthr/o/scopy• Means visual examination of a

joint using a scope.• arthr/o = joint; -scopy = using a

scope for visual examination.

The Double RRs• Suffixes beginning with two Rs

are particularly confusing.• -rrhage and –rrhagia =

abnormal excessive fluid discharge or bleeding.

• Example: hem/o/rrhage is the loss of a large amount of blood in a short time.

• -rrhaphy means “to suture or stitch”.

• Example: my/o/rrhaphy = suture a muscle.

• my/o = muscle; -rrhaphy = suture.

• To remember this suffix, think of r-r-wrap as if you were going to wrap the injury in sutures.

• -rrhea means “an abnormal flow or discharge”. Refers to the abnormal flow of most body fluids.

• Example: diarrhea = abnormally frequent loose or watery stools.

• Dia- means “through”, and –rrhea means “abnormal flow”.

• -rrhexis means “rupture.”• Example: my/o/rrhexis = rupture

of a muscle.• My/o = muscle; -rrhexis =

rupture.• To remember this suffix, think of

the x as being ready to rupture and fly apart.

Suffixes relating to “study”• -ology means “the study of”.• Example: neur/ology is the study

of the nerves.• Cardi/ology is the study of the

heart.

• -ologist means “the specialist who studies”.

• Example: neur/ologist = specialist who studies nerves.

• Cardi/ologist = specialist who studies the heart.

• Hepat/ologist = specialist who studies the liver.

Now, let’s look at prefixes….• A prefix is added to the

beginning of a word to change the meaning of that term.

• Prefixes usually, but not always, indicate location, time, or number.

Common Prefixes:• pre- means “before”.• Example: pre/natal = before

birth• post- means “after”.• Example: post/natal = after the

birth.

• dys- means “bad, difficult, or painful”.

• Example: dys/uria = difficult or painful urination.

• eu- means good, normal, well, or easy. The opposite of dys-.

• Example: eu/thyroid = a normally functioning thyroid gland.

• hyper- means “excessive or increased”.

• Example: hyper/tension means higher than normal blood pressure.

• hypo- means “deficient or decreased”. Opposite of hyper-.

• Example: hypo/tension is lower than normal blood pressure.

• inter- means “between or among”.

• Example: inter/costal means between the ribs (cost/o = ribs).

• intra- means within or inside.• Example: intra/muscular means

within the muscle.

• sub- means “under, less, or below”.

• Example: sub/costal = below the ribs.

• supra- means “above or excessive”. Opposite of sub-.

• Example: supra/costal = above or outside the ribs.

Determining Meanings on the Basis of Word Parts

• To find a word’s meaning, you must first separate it into word parts.

• You can do this by using slash marks (/) to separate them.

• Example: tonsill/ectomy

• Always start at the end of the word, with the suffix, and work toward the beginning.

• Example: tonsill/ectomy = surgical removal of the tonsils.

• As you separate the word parts, this should give you a definition of the term.

• Because some word parts have more than one meaning, it also is necessary to determine the context in which the term is being used. As used here, context means to determine which body system this term is referring to.

• If you have any doubt, use your medical dictionary to double-check the definition.

• Taber’s Medical Dictionary is the one used in this classroom, and in most healthcare facilities.

Using a Medical Dictionary• When starting to work with an

unfamiliar dictionary, spend a few minutes reviewing its use guide, table of contents, and appendices.

• If you cannot find the word on the basis of your spelling, start looking for alternative spellings based on the beginning sounds.

• Open your book to page 10.• Look at Table 1.5 at the bottom

of the page.• Let’s go over these…..• Then, close your book again.

Rules to remember…..• Frequently, there is more than

one correct way to pronounce a medical term.

• Example: arthroscopy or arthroscopy

• Both are correct; the difference is a matter of preference.

• Correct spelling is extremely important!

• Changing just one or two letters can completely change the meaning of a word – and this difference literally could be a matter of life or death for the patient.

• Abbreviations are frequently used as a shorthand way to record long and complex medical terms.

• But they can also lead to confusion and errors!

• Be very careful when using or translating an abbreviation.

• Example: BE means “below elbow” and “barium enema”!

• Because the same abbreviation may have more than one meaning, it is important that you be very careful when using or translating an abbreviation.

• To be safe, always follow this rule:

• When in doubt, spell it out!

Singular and Plural Endings• Many medical terms have Greek

or Latin origins. As a result of these different origins, there are unusual rules for changing a singular word into a plural form.

• Turn to page 12 in your book.• Let’s go over these guidelines.

Basic Medical Terms• Let’s look over at page 13 in

your textbook to learn some similar and opposite terms.

Study Break• Turn to page 15; look at the

orange box at the bottom titled “Study Break.”

• That ends this chapter!!!!