a nice way of refering to a person who is not smart or who does things that are ill-advised

See also: not the sharpest tool in the shed, a few bricks shy of a load, not playing with a full deck
Durwood: My uncle is not the brightest bulb on the porch.

Winthrop: Why do you say that?

Durwood: He saw a sign that said 'keep of the grass'... so flushed his stash o' hash down the drain.

Winthrop: Bloody 'ell!
by Hey-Johnny-Johnny June 5, 2006
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