1.VerbTo apply mental or physical effort to (something) in order to shape, form, improve, investigate, solve it, etc.
"John's in the studio working on the plans for the new house.; I've been working on this problem for several days, but I still haven't figured it out."
2.VerbTo exercise influence on someone.
"Leave it to me. I'll try to work on the boss to give us the day off."
3.VerbUsed other than figuratively or idiomatically: see work, on.