ya-yas — ONAD

ya-yas /ˈyäyäz, ˈjɑjɑz

▸ plural noun

– PHRASES
get your ya-yas out informal
enjoy yourself in an uninhibited way:

if you're looking for a way to get your ya-yas out, nothing beats karaoke

school starts for them next week, so we're getting our ya-yas out.

– ORIGIN 1970s : from Get Yer Ya-Yas Out!, the title of an album (1970) by the Rolling Stones; yas yas is a US slang term for the buttocks or anus, from ass2.