from The American Heritage® Dictionary of the English Language, 4th Edition
- n. An assistant to a chief, especially in a crime syndicate.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. An assistant to the boss of a crime family
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. an assistant or second-in-command to a chief (especially in a crime syndicate)
under- + boss, calque of the Italian sotto capo (Wiktionary)