Simple Definition of killjoy

from our Learner's Dictionary

killjoy

noun

ˈkɪlˌʤoɪ How to pronounce killjoy (audio)
plural killjoys
disapproving : a person who spoils other people's fun or enjoyment
I don't want to sound like a killjoy, but shouldn't we study tonight?

Cite this Entry

“Killjoy.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/killjoy. Accessed 15 Apr. 2026.

Copy Citation

More from Merriam-Webster on killjoy

Thesaurus: All synonyms and antonyms for killjoy

Nglish: Translation of killjoy for Spanish Speakers

Last Updated: - Entry added

More from Merriam-Webster

Word of the Day

Listen to the pronunciation of mayhem

See Definitions and Examples »

Popular in Grammar & Usage

See More

Are You Misusing These 10 Common Words?

5 Verbal Slip Ups and Language Mistakes

Is it 'nerve-racking' or 'nerve-wracking'?

The Difference Between 'i.e.' and 'e.g.'

Democracy or Republic: What's the difference?
See More

Popular in Wordplay

See More

The Longest Long Words List

The Opposite of Déjà Vu

The Words of the Week - Apr. 10

Was 'nervous Nellie' a Real Person?

Why do we say 'make a beeline'?
See More

Popular

See More

Are You Misusing These 10 Common Words?

The Longest Long Words List

The Opposite of Déjà Vu
See More

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
The Missing Letter A daily crossword with a twist
womans hand holding a green four leaf clover
Are You Feeling Lucky? Quiz A charming quiz about fortunate and unfortunate w...
See All