your, his, etc. pet hate
A source of annoyance for one; a pet peeve. Ugh, my pet hate is people who chew with their mouths open.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
your, his, etc. pet ˈhate(British English) (American English your, his, etc. pet ˈpeeve) something that you particularly dislike: She didn’t mind people smoking, but her pet hate was people blowing smoke in her face.
Farlex Partner Idioms Dictionary © Farlex 2017