pooh-pooh vs reject

pooh-pooh is not a noun while reject is a noun.

Word	Noun	Adjective	Verb	Adverb
pooh-pooh	No	No	Yes	No
reject	Yes	No	Yes	No

As verbs, pooh-pooh and reject are synonyms defined as:

Other synonyms of pooh-pooh include disdain, freeze off, scorn, spurn, turn down.

pooh-pooh (noun)	reject (noun)
	the person or thing that is rejected or set aside as inferior in quality

pooh-pooh (verb)	reject (verb)
reject with contempt	not accept something given or offered
express contempt about	dismiss from consideration or a contest
	deem wrong or inappropriate
	reject with contempt
	not accept as true
	refuse entrance or membership
	resist immunologically the introduction of some foreign tissue or organ