Top definition
Someone kind of dull, dim, unimpressive, slightly south of mediocre
You know, Joe is kind of a thirty watt bulb, barely got into community college, flunked out after 1 semester as a part time student, now barely keeps his job at the 7 Eleven.

Girl: Uh..... I'm way out of your league. Me: Yale grad, doctor. You: thirty watt bulb.
by zadok the beast April 10, 2009
Get the mug
Get a thirty watt bulb mug for your cousin José.