would have assumed the etymology of the word related to sexual innuendo. perhaps it did as well.

New York Police Department Captain Alexander S. "Clubber" Williams gave the area its nickname^[4] in 1876, when he was transferred to a police precinct in the heart of this district. Referring to the increased amount of bribes he would receive for police protection of both legitimate and illegitimate businesses there – especially the many brothels – Williams said, "I've been having chuck steak ever since I've been on the force, and now I'm going to have a bit of tenderloin."^[1][2]

The name became a generic term for a Red-light district in an American city; San Francisco, California is among the other cities having a well-known "Tenderloin District".