hew vs snag

hew is not a noun while snag is a noun.

Word	Noun	Adjective	Verb	Adverb
hew	No	No	Yes	No
snag	Yes	No	Yes	No

As verbs, snag is a hyponym of hew; that is, snag is a word with a more specific, narrower meaning than hew:

hew (noun)	snag (noun)
	an unforeseen obstacle
	an opening made forcibly as by pulling apart
	a dead tree that is still standing, usually in an undisturbed forest
	a sharp protuberance

hew (verb)	snag (verb)
strike with an axe; cut down, strike	catch on a snag
make or shape as with an axe	hew jaggedly
	get by acting quickly and smartly