wet blanket vs party pooper

wet blanket and party pooper both are nouns.

Word	Noun	Adjective	Verb	Adverb
wet blanket	Yes	No	No	No
party pooper	Yes	No	No	No

As nouns, wet blanket and party pooper are synonyms defined as:

Other synonyms of wet blanket include killjoy, spoilsport.

wet blanket (noun)	party pooper (noun)
someone who spoils the pleasure of others	someone who spoils the pleasure of others