knock 'em dead
Also found in: Acronyms.
knock (one) dead
To strongly impress one. Often used as an imperative to give encouragement. Good luck on the audition! Knock 'em dead, kid! Your design is going to knock the judges dead. They're going to swoon over it.
knock 'em deadINFORMAL
If you say that someone or something will knock 'em dead, you mean that they will impress people very much. Glamorous make-up is best reserved for evenings, or days when you want to go all out to knock 'em dead. Note: You can also say that something will knock someone dead. Their debut album is going to knock you dead. Note: The word `'em' is a form of `them' which is used in informal or non-standard English.