To stop doing something.
Look Love Albatross, we've been going for four hours now. I've come seven times. Can't we just knock it on the head?
41👍 15👎
Used if a prior arrangement is terminated by either party usually due to laziness, a lack of interest or tiredness.
Turn it in
Joe - "You still wanna go to the club tonight?"
Pete - "Nah, knock it on the head mate, im too tired!"
24👍 9👎