perk up (one's) ears(redirected from perking up his ears)
perk up (one's) ears
1. Of oneself, to become more or particularly alert, intrigued, or enthusiastic. I perked up my ears when I heard that my favorite author had a new book coming out.
2. Of someone else, to cause him or her to become so. I bet I know something that will perk up your ears: Rob is single again!