fluff vs miscarry

fluff is a noun but miscarry is not a noun.

Word	Noun	Adjective	Verb	Adverb
fluff	Yes	No	Yes	No
miscarry	No	No	Yes	No

As verbs, miscarry is a hypernym of fluff; that is, miscarry is a word with a broader meaning than fluff:

Other hypernyms of fluff include fail, go wrong.

fluff (noun)	miscarry (noun)
a blunder (especially an actor's forgetting the lines)
something of little value or significance
any light downy material

fluff (verb)	miscarry (verb)
ruffle (one's hair) by combing the ends towards the scalp, for a full effect	suffer a miscarriage
erect or fluff up	be unsuccessful
make a mess of, destroy or ruin