Cockney rhyming slang to call someone a moron. Jack of clubs is a card and card rhymes with tard.
Oi! Fix your mince pies on the jack of clubs who spilled a britney on his adams.
by Capt. Spankee Magoo June 22, 2009
An idiot, someone who does something stupid that annoys you.
'What are you doing! You jack of clubs!'
by El Chadders October 03, 2007