ventral root vs efferent

ventral root and efferent both are nouns.

Word	Noun	Adjective	Verb	Adverb
ventral root	Yes	No	No	No
efferent	Yes	Yes	No	No

As nouns, efferent is a hypernym of ventral root; that is, efferent is a word with a broader meaning than ventral root:

ventral root: one of the two roots of a spinal nerve that passes ventrally from the spinal cord and that consists of motor fibers
efferent: a nerve that conveys impulses toward or to muscles or glands

Other hypernyms of ventral root include efferent nerve, motor nerve.

ventral root (noun)	efferent (noun)
one of the two roots of a spinal nerve that passes ventrally from the spinal cord and that consists of motor fibers	a nerve that conveys impulses toward or to muscles or glands

ventral root (adjective)	efferent (adjective)
	of nerves and nerve impulses; conveying information away from the CNS