Glossary
suffix
A suffix is the part fixed to the end of a medical word, and it says what is being done or what kind of word this is — a condition, an inflammation, a procedure, a specialist.
A suffix is the part fixed to the end of a medical word, and it says what is being done or what kind of word this is: a condition, an inflammation, a procedure, a specialist. -itis means inflammation, so gastritis, nephritis and dermatitis are all inflammations, each of a different place. -ectomy means removal, so appendectomy is the removal of an appendix; -ologist names a specialist and -ology the field that specialist works in. The suffix also decides the word class, which makes it the piece to read first when a sentence needs a noun where the word is a verb. Read from the suffix back through the root to the prefix, and the word assembles itself in reverse. A suffix can change the spelling of the root it meets — a root ending in a vowel often drops it before a vowel-initial suffix — so a word that looks irregular is usually following the rule rather than breaking it.
Taught in
Related terms
- root — The root is the part of a medical word that says what the word is about — the organ, the tissue or the substance — and everything else in the word modifies it.
- combining vowel — A combining vowel — almost always o — is the vowel placed between a root and a suffix when the suffix starts with a consonant.
- word part — A word part is a prefix, root, suffix or combining vowel — one of the pieces a medical word is built from.
Source: MedlinePlus (US National Library of Medicine) consumer guidance on understanding medical words, which the vocabulary guide follows for the prefix, root, suffix and combining-vowel system. US federal government material, not subject to copyright in the United States. Every definition and example above was written for this course in our own words; no dictionary or glossary text is reproduced. (MedlinePlus accessed 2026-10-27; definitions written 2026-10-27)