dunk vs slam-dunk

dunk is a noun but slam-dunk is not a noun.

Word	Noun	Adjective	Verb	Adverb
dunk	Yes	No	Yes	No
slam-dunk	No	No	Yes	No

As verbs, slam-dunk is a hyponym of dunk; that is, slam-dunk is a word with a more specific, narrower meaning than dunk:

dunk (noun)	slam-dunk (noun)
a basketball shot in which the basketball is propelled downward into the basket

dunk (verb)	slam-dunk (verb)
dip into a liquid while eating	make a slam dunk; shoot a basketball in a slam dunk
immerse briefly into a liquid so as to wet, coat, or saturate	make a forceful move against
make a dunk shot, in basketball