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!"