get your oats
get (one's) oats
To have sexual intercourse, especially frequently. Primarily heard in UK. Bill is hardly ever home anymore—he must be getting his oats now that he's single again.
get your oatshave sexual intercourse. informal
1965 William Dick A Bunch of Ratbags I was kissing her excitedly and passionately… Cookie, you're gonna get your oats tonight for sure, I thought to myself.