Not The Brightest Bulb On The Porch Edit Meaning

1.

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!

See dumb, silly, stupid, unintelligent, touched