crest vs top

crest and top both are nouns.

Word	Noun	Adjective	Verb	Adverb
crest	Yes	No	Yes	No
top	Yes	Yes	Yes	No

As nouns, top is a hypernym of crest; that is, top is a word with a broader meaning than crest:

Other hypernyms of crest include top side, upper side, upside.

As nouns, crest and top are synonyms defined as:

crest and top: the top or extreme point of something (usually a mountain or hill)

Other synonyms of crest include crown, peak, summit, tip.

crest (noun)	top (noun)
a showy growth of e.g. feathers or skin on the head of a bird or other animal	a garment (especially for women) that extends from the shoulders to the waist or hips
(heraldry) in medieval times, an emblem used to decorate a helmet	covering for a hole (especially a hole in the top of a container)
the center of a cambered road	a canvas tent to house the audience at a circus performance
the top line of a hill, mountain, or wave	a conical child's plaything tapering to a steel point on which it can be made to spin
the top or extreme point of something (usually a mountain or hill)	platform surrounding the head of a lower mast
	the greatest possible intensity
	the highest or uppermost side of anything
	the upper part of anything
	the top or extreme point of something (usually a mountain or hill)
	the highest level or degree attainable; the highest stage of development
	the first half of an inning; while the visiting team is at bat

crest (adjective)	top (adjective)
	situated at the top or highest position

crest (verb)	top (verb)
reach a high point	be the culminating event
lie at the top of	finish up or conclude
	cut the top off
	strike (the top part of a ball in golf, baseball, or pool) giving it a forward spin
	pass by, over, or under without making contact
	reach or ascend the top of
	provide with a top or finish the top (of a structure)
	be superior or better than some standard
	be at the top of or constitute the top or highest point
	be ahead of others; be the first