someone's ears are flapping
(someone's) ears are flapping
Someone is listening, or trying to listen, to the details of a private conversation. Let's finish this conversation in the meeting room in case people's ears are flapping nearby.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
someone's ears are flappingsomeone is listening intently in order to overhear something not intended for them. informal
Farlex Partner Idioms Dictionary © Farlex 2017