smelling vs snuff

smelling and snuff both are nouns.

Word	Noun	Adjective	Verb	Adverb
smelling	Yes	Yes	No	No
snuff	Yes	Yes	Yes	No

As nouns, snuff is a hyponym of smelling; that is, snuff is a word with a more specific, narrower meaning than smelling:

Other hyponyms of smelling include sniff.

smelling (noun)	snuff (noun)
the act of perceiving the odor of something	sensing an odor by inhaling through the nose
	finely powdered tobacco for sniffing up the nose
	a pinch of smokeless tobacco inhaled at a single time
	the charred portion of a candlewick

smelling (adjective)	snuff (adjective)
(used with `of' or `with') noticeably odorous	snuff colored; of a greyish to yellowish brown

smelling (verb)	snuff (verb)
	inhale (something) through the nose
	sniff or smell inquiringly