a comeback to a question or insult. it is beautiful in its simplicity in that those two words will imply that the person's mother is fat, baggy, saggy, ugly and would probably simulate coitis with anything that got in her way. the only acceptable comebacks to a display of 'yourmummery' are shown below:
Cardy: Hey, what's that smell?
Daly: Your mum.
Cardy: Your face.
Daly: Your mum's face.
(on NO account bring 'your dad' into this - that's just rude.)
The particular giggles you get when you've schmoked tooooo much skunk. Uncontrolable laughing fits that usually cause the sufferer to hide their face in their jumper. When you're got the genoobies EVERYTHING is funny as hell.
"Hahahahahahaha... oh shit... hahahaha... my mum's coming home... hahahahahaha... I've got the genoobies... hahahaha!"