Real Dictionary

oversteer in American English
the tendency of a motor vehicle, esp. a race car, to have its rear tires slide outward on a turn
intransitive verb: to undergo or handle with an oversteer, esp. excessively
noun: handling of an automotive vehicle that causes turns that are sharper than the driver intends because the rear wheels slide to the outside of the turn before the front wheels lose traction

oversteer in Automotive Engineering
noun: Oversteer is the tendency of a vehicle to turn more sharply than expected.

oversteer in British English
(of a vehicle) to turn more sharply, for a particular turn of the steering wheel, than is desirable or anticipated
noun: the tendency of a vehicle to oversteer