A person or thing who thinks he is brighter than he is. Or, one who would like to be brighter than he is. Flat Champagne.
The Vice-President of the Condo is a dim bulb. We call him Dimmy. The only Champagne he drinks is flat like a dim bulb.
by Knockings July 11, 2011
a very stupid person
Gary must be the dim bulb in that group.
by familyguy April 26, 2005