smoke vs coffin nail

smoke and coffin nail both are nouns.

Word	Noun	Adjective	Verb	Adverb
smoke	Yes	No	Yes	No
coffin nail	Yes	No	No	No

As nouns, coffin nail is a hyponym of smoke; that is, coffin nail is a word with a more specific, narrower meaning than smoke:

Other hyponyms of smoke include cigar, butt, cigaret, cigarette, fag.

smoke (noun)	coffin nail (noun)
the act of smoking tobacco or other substances	finely ground tobacco wrapped in paper; for smoking
(baseball) a pitch thrown with maximum velocity
tobacco leaves that have been made into a cylinder
street names for marijuana
something with no concrete substance
an indication of some hidden activity
a cloud of fine particles suspended in a gas
a hot vapor containing fine particles of carbon being produced by combustion

smoke (verb)	coffin nail (verb)
inhale and exhale smoke from cigarettes, cigars, pipes
emit a cloud of fine particles