WordNet sense 1 (a series of actions advancing a principle or tending toward a particular end):

campaign, cause, crusade, drive, movement

WordNet sense 2 (use of physical or mental energy; hard work):

exertion, sweat, travail, elbow grease

WordNet sense 3 (earnest and conscientious activity intended to do or accomplish something):

attempt, endeavor, try, endeavour

WordNet sense 4 (a notable achievement):

deed, exploit, feat, exploit