The act of hiding a portion of your chips in a pocket while playing l Poker then going 'all in'. Then, after you lose, taking the concealed poker chips from the pocket and placing them on the table like nothing happened.
Paul: "Hey Pat, didn't Ben go 'all in' and lose just a minute ago?"
Used to describe an activity which involves one person looking to have relations (sexual or intimate) with a minor.
Originates from the word nonce meaning pervert
Jeffrey: Hey Andrew, want to go out noncing with me and Ghislaine?
Prince Andrew: Well, I was going to go to Pizza Express in Woking, but sure, why the heck not.
When you, as a younger man/woman/whatever, groom an elder gentleman/gentlewoman/gentlewhatever into pursuing yourself despite their moral objections. Hence turning them into a nonce.
Person 1: Did you hear about what happened to Lewis?
Person 2: Ali, through reverse noncing, got him into bed Person 1: No fucking way, Lewis is like 10 years older than him and not into younger men.