a semi-legendary English medieval outlaw, reputed to have robbed the rich and helped the poor. Although he is generally associated with Sherwood Forest in Nottinghamshire, it seems likely that the real Robin Hood operated in Yorkshire in the early 13th century.
(as noun a Robin Hood) a person considered to be taking from the wealthy and giving to the poor:a latter-day Robin Hood, he takes from the exchequers of the rich West to provide capital for the poor East
Robin Hood in other Oxford dictionaries
Definition of Robin Hood in the US English dictionary