child's play, cinch, duck soup, piece of cake, pushover, breeze, walkover, picnic, snap - any undertaking that is easy to do; "marketing this product will be no picnic"

work - activity directed toward making or doing something; "she checked several points needing further work"

adventure, dangerous undertaking, escapade, risky venture - a wild and exciting undertaking (not necessarily lawful)

assignment - an undertaking that you have been assigned to do (as by an instructor)

baby - a project of personal concern to someone; "this project is his baby"

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

labor of love, labour of love - productive work performed voluntarily without material reward or compensation

endurance contest, marathon - any long and arduous undertaking

no-brainer - anything that requires little thought

proposition - a task to be dealt with; "securing adequate funding is a time-consuming proposition"

large order, tall order - a formidable task or requirement; "finishing in time was a tall order but we did it"

venture - any venturesome undertaking especially one with an uncertain outcome

Manhattan Project - code name for the secret United States project set up in 1942 to develop atomic bombs for use in World War II

craft, trade - the skilled practice of a practical occupation; "he learned his trade as an apprentice"