A phrase expressed after someone makes a fool out of them selves after professing their undying worth, or intelligence.Pronounced "Hum-bal-ie Dum-bal-ie"
Man, that guy was arrogant, but after taking a fall like that he just looked humbly dumbly.
Thumb me dumbly is the acting of taking the nearest mentally challenged person (or group of persons depending on how fucked up you are) and having he/she/them insert their thumbs into your anal cavity
Guy 1: so what did you get up to last weekend bro?
Guy 2: I went to the loony bin and got a few retards to thumb me dumbly
Guy 1: you’re a sick little cunt you are