Abbreviated form of the expression ''are you dumb'', often used by Londoners when someone makes a stupid remark or when someone acts like a complete fool.
Friend 1: oi fam look at dat peng ting i would bang her 10/10
Friend 2: is it? lemme check....
*5 seconds later*
Friend 2: bruv rudum look at her butterface she aint buff
Friend 2: is it? lemme check....
*5 seconds later*
Friend 2: bruv rudum look at her butterface she aint buff
by swagswagswerve September 22, 2015