overturn something—
1. throw smth. over with violence; cause smth. to fall over:
- She overturned the chairs and hurled the cushions about.
2. (of a law, verdict, etc.) abolish or invalidate:
- Anti-abortion forces have been organizing to overturn the decision of the Supreme Court.
turn something over—
1. turn smth. upside down:
- Mr. Campion turned over the battered cardboard-backed book…. “Whose is it?”
2. leaf through the pages of a document, etc.:
- He turned over the pages with the hopeless air of a connoisseur examining an objet d’art.
3. (also: turn something over in one’s mind) mentally review smth.:
- Going home that night Dr. Renshaw turned over the facts of the case.
4. (sl.) ransack a house, etc.; steal goods from a place:
- Half the school is on probation for turning over a supermarket.
5. (of money or merchandise) handle in business:
- Our shop turns over ten thousand dollars a week, but we only make a few hundred dollars profit.