From Longman Dictionary of Contemporary Englishprick (up) your earsprick (up) your earsLISTENif you prick up your ears or your ears prick up, you listen carefully because you have heard something interesting Jay pricked up his ears when I mentioned a vacation. → prick
Examples from the Corpus
prick (up) your ears• Henry pushed his door open a crack, and pricked up his ears.• The horse, scenting home and supper, pricked his ears and stepped out.• I pricked up my ears, and sure enough, the sound was getting louder.• The boy pricked up his ears, because, as it happened, so they were this earth.• I pricked my ears up on that one. 