to coin a phrase

Từ điển Oxford Advanced Learner 8th

to coin a ˈphrase idiom
1. used to introduce a well-known expression that you have changed slightly in order to be funny
•Tasting is believing, to coin a phrase! (= the usual phrase is ‘seeing is believing’).
2. used to show that you are aware that you are using an expression that is not new
• Oh well, no news is good news, to coin a phrase.
Main entry: ↑coin_idiom