Essential Medical English Vocabulary: Word Formation (N–O)

Medical English N–O: Prefixes, Suffixes, and Word-Building

Overview

This section covers medical vocabulary beginning with N and O, focusing on common prefixes, suffixes, and processes used to form clinical and technical terms. It helps you recognize meanings, build new terms, and decode unfamiliar words.

Common prefixes (N–O)

• neo- — new (e.g., neoplasm: new growth)
• non- / neo- — not / new (non- as negation: noninvasive)
• nor- — normal, relating to norepinephrine (e.g., noradrenaline as a root in pharmacology)
• oligo- — few, scanty (e.g., oliguria: low urine output)
• omni- — all (rare in clinical terms; see omnivore in biology)
• ortho- — straight, correct (e.g., orthodontics, orthopedic)
• oto- — ear (e.g., otology, otitis)

Common suffixes (N–O)

• -nesia — relating to memory (e.g., amnesia; less common with N)
• -nomy — law, knowledge, classification (e.g., taxonomy; eponymous in specialized usage)
• -osis — condition, diseased state (e.g., necrosis, narcosis, onychosis)
• -otomy — cutting into, incision (e.g., tracheotomy, lobotomy)
• -ostomy — creating an opening (e.g., colostomy, ileostomy)
• -opathy — disease (e.g., neuropathy, osteopathy)
• -oma — tumor, swelling (e.g., melanoma, neuroma)

Word-building patterns

• Root + suffix: neuropathy = neur- (nerve) + -pathy (disease).
• Prefix + root: oliguria = oligo- (few) + -uria (urine).
• Prefix + root + suffix: osteoarthritis = osteo- (bone) + arthr- (joint) + -itis (inflammation).
• Combining forms often use a linking vowel (usually -o-): cardiology (cardi + o + logy).

Examples (N–O) with breakdowns

• Necrosis = necr- (dead tissue) + -osis (condition) — tissue death.
• Neoplasm = neo- (new) + -plasm (formation) — new growth, tumor.
• Neurology = neur- (nerve) + -ology (study) — study of the nervous system.
• Nephrectomy = nephr- (kidney) + -ectomy (removal) — surgical removal of a kidney.
• Nystagmus = nystag- (to nod) + -mus (condition) — involuntary eye movement.
• Oncology = onc- (tumor) + -ology (study) — study of tumors/cancer.
• Onychomycosis = onych- (nail) + myc- (fungus) + -osis (condition) — fungal infection of nails.
• Osteopathy = osteo- (bone) + -pathy (disease/treatment system) — bone-related disease or a medical approach.
• Otitis = ot- (ear) + -itis (inflammation) — ear inflammation.
• Oophorectomy = oophor- (ovary) + -ectomy (removal) — removal of an ovary.

Tips for learning and practice

1. Group by prefix/suffix: study words sharing the same affix to see patterns.
2. Break down unfamiliar words: identify prefix, root, suffix; look up each part.
3. Use flashcards: include breakdown and definition on each card.
4. Create practice sentences: reinforce meaning in context.
5. Focus on combining vowels: recognize when -o- links elements and when it’s part of the root.

Short practice exercise (self-test)

• Break down and define: nephrology, neurasthenia, oncogene, oophoritis, oliguria.

Answers (brief):

• Nephrology: nephr- (kidney) + -ology (study).
• Neurasthenia: neur- (nerve) + asthenia (weakness).
• Oncogene: onc- (tumor) + -gene (producer/producer of).
• Oophoritis: oophor- (ovary) + -itis (inflammation).
• Oliguria: oligo- (few) + -uria (urine).

If you want, I can produce a printable one-page cheat sheet or a 20-word quiz with answers.