Glossary
part of speech
A part of speech is the grammatical class a word belongs to — noun, pronoun, verb, adjective, adverb, preposition, conjunction or interjection — and it decides the job the word does.
A part of speech is the class a word belongs to according to the job it does in a sentence: noun (a person, place, thing or idea), pronoun (stands in for a noun), verb (an action or a state), adjective (describes a noun), adverb (describes a verb, an adjective or another adverb), preposition (shows a relationship such as in, on, between), conjunction (joins words or clauses) and interjection (an exclamation).
The same word can belong to more than one class. Light is a noun in the light is on, an adjective in a light bag and a verb in light the fire, so the class is decided by the sentence, not by the word alone.
That is why this matters on a vocabulary question. One of the wrong choices is frequently the right meaning written as the wrong part of speech — a noun offered where the sentence needs an adjective — and the difference is invisible unless you name the class before you compare the definitions. Find the class the sentence demands, then check each choice against it. Two of the four choices are usually eliminated on the part of speech alone.
Taught in
Related terms
- prefix — A prefix is a word part added to the front of a root that changes its meaning — un-, re-, pre-, sub- and trans- among them. Learning a few unlocks dozens of words.
- suffix — A suffix is a word part added to the end of a root. It can change the meaning and, unlike a prefix, it usually changes the word's part of speech.
- distractor — A distractor is a wrong answer choice written to look plausible. ASVAB distractors are near misses — related meanings, wrong parts of speech, or a straight reversal — not nonsense.
Source: Official ASVAB — subtest descriptions (what each subtest asks) and the CAT-ASVAB scored-question counts (accessed 2026-09)