turn (something) upside down

to change something completely.

His experience in the war turned his world upside down.

The crash of the dot-com companies turned lives upside down.

Related vocabulary: turn something on its head

• What's someone's game?
• What's something in aid of?
• What's something when it's at home?
• What's the big idea?
• What's the deal?
• What's the magic word?
• what's the world coming to
• What's the world coming to?
• What's when it's at home?
• What's your poison?
• what the hell
• what will become of
• what will become of someone
• what will become of something
• What you don't know won't hurt .
• What you don't know won't hurt you.
• wheel and deal
• wheeler-dealer
• wheel has come full circle.
• wheel has turned full circle.
• wheeling and dealing
• wheels are turning
• when all is said and done
• when back is turned
• when hell freezes over