Four Hour Erection

A side-effect of male-enhancement medicine. Results in extreme discomfort if you are wearing especially tight pants. Not that any one person writing any definitions specifically has done that. Extremely obvious no matter what clothes you're wearing. Can be spotted from long distances.

Sexually inept man: Damn, I've had this erection for four hours!
Me: You shouldn't have taken Viagra. Your pants look like a tent at a circus.
SIM: Man, I hate four hour erections