adjective Slang: Usually Vulgar. (of a man) having a large penis.

What does it mean if someone is well hung?

adjective. If someone says that a man is well-hung, they are saying that he has a large penis. [humorous]

Where did the expression Well Hung come from?

"Well hung."

(As if voiding your bowels in front of the whole town wasn't dispiriting enough.) Put simply, many got an erection, and often ejaculated. So the theory is that to be "well hung" originated from that "venereal event," as they might have put it in the eighteenth-century.