Urban Dictionary describes a numpty as thus:
1. An idiot, a silly person.
2. A person who never has or never will have a fucking clue what he is doing.
3. A Scottish term, short for numb-skull.
4. Dialect, chiefly Scots. A bumbling fool or one who is intellectually challenged.
5. A person so stupid they are incapable of understanding the simplest of things.
6. Numpty first surfaced on the terraces of west of Scotland football grounds, many, many years ago. A player who couldn't hit a cow's arse with a shovel would be a fucking numpty.
Personally I love the phonetics of it. To call somebody a numpty aloud is one of life's joys.
Haven't googled for other meanings, but in the UK a nonce is slang for a paedophile.
Yeah my wife is younger but not that much younger lol
Sent from my fucking phone.