A secret partnership or agreement, usually for something dishonest or sneaky (always used in the phrase 'in cahoots').
Possibly from French 'cahute' meaning hut or cabin, or from 'cohort' meaning a group or band of people. The exact origin is disputed, but it emerged in American English in the 19th century.
Despite its modern American slang flavor, 'cahoots' might come from French settlers in Louisiana—it's one of hundreds of words English borrowed from French speakers on the frontier, most now forgotten.
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