commissure vs pathway

commissure and pathway both are nouns.

Word	Noun	Adjective	Verb	Adverb
commissure	Yes	No	No	No
pathway	Yes	No	No	No

As nouns, pathway is a hypernym of commissure; that is, pathway is a word with a broader meaning than commissure:

commissure: a bundle of nerve fibers passing from one side to the other of the brain or spinal cord
pathway: a bundle of myelinated nerve fibers following a path through the brain

Other hypernyms of commissure include nerve pathway, nerve tract, tract.

commissure (noun)	pathway (noun)
a bundle of nerve fibers passing from one side to the other of the brain or spinal cord	a trodden path
	a bundle of myelinated nerve fibers following a path through the brain