SPOILSPORT
Meaning of SPOILSPORT in English
spoil ‧ sport /ˈspɔɪlspɔːt $ -spɔːrt/ BrE AmE noun [countable] informal
someone who spoils other people’s fun:
Don’t be such a spoilsport.
Longman Dictionary of Contemporary English.
Longman - Словарь современного английского языка.
2012