Cartel
Etymology
From French cartel, from Italian cartello, "a placard or written challenge," a diminutive of carta, "card, paper" (from Latin charta). It first meant a written agreement between enemies, such as a truce; the sense drifted to a formal pact among businesses to cooperate rather than compete.
noun · /kar-TEL/
A group of nominally competing producers who secretly agree to fix prices, limit supply, or divide up a market.
What it names
It names how rivals can imitate a monopoly without merging — by quietly coordinating instead of competing, so everyone charges more.
Example
Regulators broke up the cartel after discovering the manufacturers had agreed to keep prices high.
Related idea
A monopoly is one firm dominating alone; a cartel is several firms colluding to act as if they were one.