put the knife in
To do or say something especially critical, unpleasant, or mean-spirited, especially to someone who is already vulnerable or weak. John seems genuinely remorseful for what happened. There doesn't seem to be any reason to put the knife in at this point. And then he really put the knife in by telling me that he'd only pretended to like my writing.
stick the knife in
To be, do, or say something especially critical, unpleasant, or mean-spirited, especially to someone who is already vulnerable or weak. John seems genuinely remorseful for what happened. There doesn't seem to be any reason to stick the knife in at this point. And then he really stuck the knife in by telling me that he'd only pretended to like my writing.
Farlex Dictionary of Idioms. © 2024 Farlex, Inc, all rights reserved.
put the knife in
or stick the knife in
mainly BRITISHIf someone puts the knife in or sticks the knife in, they deliberately do or say things which will upset another person or cause problems for them. Every time he applied for a job, someone put the knife in and made sure Jack's background became known. BBC colleagues — often eager to stick the knife in — defended her yesterday.
Collins COBUILD Idioms Dictionary, 3rd ed. © HarperCollins Publishers 2012