Noun

1. The head of a crime syndicate, a high ranking criminal.

   An underworld Mr Big who built up a ruthless crime empire in Greater Manchester was jailed indefinitely yesterday. (Lancashire News 5th Jan 07).

   Defence lawyers critical of 'Mr. Big' police stings. CBCNEWS, 27 Dec 06.

   ...by the end of the novel, Mike (Hammer) has rescued Velda, killed the Mafia's sinister Mr Big, and recovered the stash of drugs..." Hardboiled Hollywood, Max DeCharne. P84.