enterprise, endeavor, endeavour

a purposeful or industrious undertaking (especially one that requires effort or boldness); "he had doubts about the whole enterprise"

• racket, fraudulent scheme, illegitimate enterprise — an illegal enterprise (such as extortion or fraud or drug peddling or prostitution) carried on for profit
• forlorn hope — a hopeless or desperate enterprise
• business activity, commercial activity — activity undertaken as part of a commercial enterprise

• undertaking, project, task, labor — any piece of work that is undertaken or attempted