poseur vs poser

poseur and poser both are nouns.

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

As nouns, poseur and poser are synonyms defined as:

poseur and poser: a person who habitually pretends to be something he is not

poseur (noun)	poser (noun)
a person who habitually pretends to be something he is not	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