When one does not use their brain. When something unbeleivebly stupid happens that you cant take it and you just yell "DUMB AS HELL". Ghetto. When your parent says something that makes no sense whatsoever so you say You dumb as hell". Making fun of someone who cant talk. When you watch Napoleon Dynamite. When you see a VW with eyelashes. When you see a pimped out PT Cruiser with the flames.
If you've tacked on an after market wing spoiler to your beater car then your either incredibly confused or just "DUMB AS HELL".

Mom: "How do i send this text?"
Child: "Girl You Dumb As HELL"

Friend 1: "I think I'm Pregnant..."
Friend 2: "Girl You Dumb As HELL"
by youdumbashell December 29, 2011
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said by Conner Temple Tv.

He Called Me Dumb
"Wheres the Gc" "U Dumb As Hell Boy"
by fouledanchors June 23, 2022
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