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1. dumb down
to make stupider; reduce the intelligence of
Listening to George W. Bush really dumbed me down.

(dumb down)
2. dumb down
What happens to people who learn definitions from this retarded site.
I go to urbandictionary daily to dumb down myself with retarded and/or completely incorrect definitions.
3. Dumb Down
To dumb down is an alternate way to say you're doing "downer" drugs (i.e. opiates, weed, etc)
Time to dumb down boys!

Guy 1: What you up to man?
Guy 2: 'bout to dumb down, what's good with you?
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