A strong yet playful expression used to tell someone to get lost, as they are either; a liar, chatting shit, being annoying, or you don't want them to be around you.
More commonly used in Scotland.
"Want to head to Revolution for a couple of drinks tonight?"
"Grab a knob mate, of course I don't!"

"I did so well in that exam man!"
"Aye right you did, away and grab a knob."
by Diego Milito March 5, 2016
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An amazing 24 hour period where anyone is allowed to grab anyones knob and bollocks (Dick). Take advantage of this day for it only comes once a year on april 16
by Bigboyseb April 12, 2018
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