Complainer

/kəmˈpleɪnər/

Synonyms

  • grievant
  • grumbler
  • moaner
  • queryer
  • whiner

Slang Meanings

Debbie Downer
She's such a Debbie Downer, always being a complainer at parties.
Buzzkill
Don't be a buzzkill; no one wants to hear your complaints.