1 turn something upside down | Definition of turn something upside down

turn (something) upside down

idiom

Definition of turn (something) upside down

1 : to turn (something) so that the top is at the bottom and the bottom is at the top To remove the plant, turn the pot upside down and tap gently on the bottom to loosen it.
2 informal : to make (something) very untidy I turned the room upside down looking for my car keys. The house was turned upside down while the renovations were underway. often used figuratively His whole world was turned upside down when his mother died.