someone who emulates good ole albus dumbledore from harry potter. This can be done in numerous ways:
1) being very hairy. this does not just have to be in the beard department. it can be eyebrows, nostrils, ears or err..anywhere else.
2) specs
3) a quivvering voice - very popular amongst the aging.
4) gowns/robes
5) tendancy to get their wand out and flash it around a bit too much
6) walking with a hunch/eccentric stride
7) generally acting like someone who believes they own a whole magical realm yet having the assetts of an old man.

these are only a few ways to identify a dumble.
dumble-pube can also be used to describe anything wispy and grey that looks unlikely to be a dumble-beard.

n. A short, fat, slow man with little to no grasp on the workings of technological devices, though he is "in the field".

v. To royally fuck up anything and everything one does.

SILLY BITCH.urinates in public

Dumble is an Amplifier for electric guitar that most can't afford. Played by Robben Ford and John Mayer among others