A noun referring to one who most likely has, will, or is engaging in an activity that is idiotic in nature when compared to everyone else's current activity. Much like how a group of sober people would perceive a drunk person.
"I'm going to throw that fluorescent light bulb"-Alex
"Don't throw it"- everyone else
Alex throws the light bulb and it shatters.
"Don't move police. I'm going to watch you clean that up"-Old Retired Cop
"Way to go rum-dumb"-Josh

by Peter LoPresti March 13, 2008

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Top Definition
An idiot due to their over consumption of alcohol over the years. One who has pickled themself.
Get outta here you freakin Rum Dumb, or I'll call the cops!
by biffula November 26, 2007

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Drunk from consuming Rum.
He is such a "rum dumb" from drinking rum all the time.
by MrFreeman88 March 08, 2004

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The Urban Dictionary T-Shirt

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