party pooper
noun
RareNot in standard dictionaries
1
One who dampens fun; especially, one who declines to participate in or enjoy a party or some other group activity; one who does not agree with the opinions of a group.
Thesaurus
#informal
One who dampens fun; especially, one who declines to participate in or enjoy a party or some other group activity; one who does not agree with the opinions of a group.