cartel

Definition from Nolo’s Plain-English Law Dictionary

A group of independent corporations or other entities that join together to fix prices, control distribution, or reduce competition. For exmple, OPEC (Organization of Petroleum Exporting Countries) is an intergovernmental organization that represents 13 oil producing countries. Many private (nongovernmental) cartels operate behind a veil of secrecy, particularly because they are illegal under United States antitrust laws (the Sherman and Clayton Acts).

Definition provided by Nolo’s Plain-English Law Dictionary.