The adjective antitrust describes a kind of law or rule that protects fairness and competition in business. Antitrust laws are intended to stop companies from forming monopolies.
An antitrust attorney specializes in business law, and the rules and regulations that keep competition between businesses fair and equal. One example of an antitrust violation is price fixing, when different companies conspire to keep prices high for their customers. The term antitrust has been around since the 1890s, when the Sherman Act was passed, prohibiting business activities that harmed competition.