in/under no circumstances
in no circumstances
Never; in no case or situation; irrespective of events or conditions. In no circumstances are you allowed to drive home after you've had more than one drink! I'm sorry for my sudden resignation, but in no circumstances will I work for some sexist manager like him.
under no circumstancesand not under any circumstances
Fig. absolutely never. Andy: Under no circumstances will I ever go back there again! Rachel: Why? What happened? Sue: Can I talk you into serving as a referee again? Mary: Heavens, no! Not under any circumstances!
in/under no circumstancesused to emphasize that something should never happen or be allowed: Under no circumstances should you lend Paul any money. ♢ Don’t open the door to strangers in any circumstances.
under no circumstances
In no case; never.