fiber bundle vs nervus

fiber bundle and nervus both are nouns.

Word	Noun	Adjective	Verb	Adverb
fiber bundle	Yes	No	No	No
nervus	Yes	No	No	No

As nouns, nervus is a hyponym of fiber bundle; that is, nervus is a word with a more specific, narrower meaning than fiber bundle:

fiber bundle: a bundle of fibers (especially nerve fibers)
nervus: any bundle of nerve fibers running to various organs and tissues of the body

Other hyponyms of fiber bundle include fornix, trigonum cerebrale, nerve.

fiber bundle (noun)	nervus (noun)
a bundle of fibers (especially nerve fibers)	any bundle of nerve fibers running to various organs and tissues of the body