organized crime

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Widespread criminal activities, such as prostitution, interstate theft, or illegal gambling, that occur within a centrally controlled formal structure.
2. n. The people and the groups involved in such criminal activities.

Wiktionary

1. n. A set of large criminal organizations (often competing for markets and territories) that deal in illegal goods and services.
2. n. The crimes perpetrated by those organizations.

GNU Webster's 1913

1. n. Groups of persons organized for illegal purposes, such as bootlegging, conducting illegal gambling, loansharking, extortion, etc.; -- a general term encompassing most forms of criminal groups, but especially those that are consolidated into “families” more or less recognizing each other's different regions of operation; sometimes considered synonymous with the mafia or the syndicate.

WordNet 3.0

1. n. underworld organizations