1 Word Parts and Rules

Medical terms are built from word parts. Those word parts are prefix, word root, suffix, and combining form vowel. When a word root is combined with a combining form vowel the word part is referred to as a combining form.

Identifying Word Parts in Medical Terms

By the end of this book, you will have identified hundreds of word parts within medical terms. Let’s start with some common medical terms that many non-medically trained people may be familiar with.

Examples

Osteoarthritis
Oste/o/arthr/itis – Inflammation of bone and joint.
Oste/o is a combining form that means bone
arthr/o is a combining form that means joint
-itis is a suffix that means inflammation

Intravenous
Intra/ven/ous – Pertaining to within a vein.
Intra- is a prefix that means within
ven/o – is a combining form that means vein
-ous is a suffix that means pertaining to

Notice, when breaking down words that you place slashes between word parts and a slash on each side of a combining form vowel.

Language Review

Before we begin analyzing the rules let’s complete a short language review that will assist with pronunciation and spelling.

Short Vowels
a, e, i, o, u, and sometimes y are indicated by lower case.

Long Vowels
A, E, I, O, U are indicated by upper case.

Consonants
Consonants are all of the other letters in the alphabet. b, c, d, f, g, h, j, k, l, m, n, p, q, r, s, t, v, w, x, and z.

Language Rules

Language rules are a good place to start when building a medical terminology foundation. Many medical terms are built from word parts and can be translated literally. At first, literal translations sound awkward. Once you build a medical vocabulary and become proficient at using it, the awkwardness will slip away. For example, suffixes will no longer be stated and will be assumed. The definition of intravenous then becomes within the vein.

Since you are at the beginning of building your medical terminology foundation, stay literal when applicable. It should be noted that as with all language rules there are always exceptions and we refer to those as rebels.

Language Rules for Building Medical Terms

1. When combining two combining forms, you keep the combining form vowel.
2. When combining a combining form with a suffix that begins with a consonant, you keep the combining form vowel.

Examples

• Following rule 1, when we join combining form gastr/o (meaning stomach) with the combining form enter/o (meaning intestines) we keep the combining form vowel o.
• Following rule 2, when we join the combining form enter/o (meaning intestines) with the suffix -logy (that starts with a suffix and means the study of) we keep the combining form vowel o.

Examples

• Following rule 3, notice that when combining the combining form ven/o (meaning vein) with the suffix -ous ( that starts with a vowel and means pertaining to) we drop the combining form vowel o.
• Following rule 4, the prefix intra- (meaning within) is at the beginning of the medical term with no combining form vowel used.

Examples

• Following rule 5, notice that I start with the suffix -ous (that means pertaining to) then we work left to right starting with the prefix Intra- (meaning within) and the combining form ven/o (meaning vein).
• Notice that we have used two different definitions that mean the same thing.
• In these examples we do not have the context of a full sentence. For the purpose of building a medical terminology foundation either definition is accepted.

Word part at the beginning of a medical term that changes the meaning of the word root.

The foundational meaning of a word

A word part added to the end of a word that changes the meaning of the word root

The combining form vowel is used to join word parts and to ease pronunciation. The most common combining form vowel is an "o," but sometimes it is an "i" or an "e".

A word root with a combining form vowel

Follows the rules exactly

Word parts that do not fit within the language rules

additional words that makes the definition complete.

License

Medical Terminology for Healthcare Professions Copyright © 2020 by Andrea Nelson and Katherine Greene is licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted.