1An agreement or combination by two or more individuals to commit a crime or to commit a lawful act by unlawful means. Making the agreement is a crime, even if the unlawful act that is planned is never performed, but most states require overt action by one of the conspirators to further the conspiracy before the making of the agreement becomes criminal. A conspiracy to harm someone is also a tort. Also called partnership in crime. See also tortfeasor, concert of action rule, accessory, accomp...