poser vs stumper

poser and stumper both are nouns.

Word	Noun	Adjective	Verb	Adverb
poser	Yes	No	No	No
stumper	Yes	No	No	No

As nouns, poser and stumper are synonyms defined as:

poser and stumper: a particularly difficult or baffling question or problem

Other synonyms of poser include sticker, toughie.

poser (noun)	stumper (noun)
a particularly difficult or baffling question or problem	a particularly difficult or baffling question or problem
a person who poses for a photographer or painter or sculptor
a person who habitually pretends to be something he is not