endeavor

(noun) a purposeful or industrious undertaking (especially one that requires effort or boldness). Synonyms: enterprise, endeavour. Example: "He had doubts about the whole enterprise."

(noun) earnest and conscientious activity intended to do or accomplish something. Synonyms: attempt, effort, endeavour, try. Examples: "Made an effort to cover all the reading material." "Wished him luck in his endeavor." "She gave it a good try."

(verb) attempt by employing effort. Synonyms: endeavour, strive. Example: "We endeavor to make our customers happy."