Definition, Meaning & Synonyms

not-play-with-a-full-deck

idiom
/nɒt pleɪ wɪð ə fʊl dɛk/
Definition
To be mentally unstable or irrational.
Examples
  • After hearing his bizarre theories, I started to think he might not be playing with a full deck.

  • She said some strange things last night; I wonder if she’s not playing with a full deck.

Meaning
This phrase suggests that a person may not be thinking clearly or may be lacking in some mental faculties, akin to not having all the necessary cards in a deck for playing a game.
Synonyms
  • not all there
  • off one’s rocker
  • not quite right