A rotary mower is a unit of powered machinery that uses a rotating blade or blades to cut vegetation.
In agriculture a rotary mower takes the form of a piece of tractor machinery that is often pulled behind the tractor and powered by the Power take-off; it uses thick blades of sharpened metal to cut thick grass, heavy bushes, weeds, and small trees. Due to the high torque and power associated with the implement, shields made of hanging heavy chain or thick vinyl or rubber are often provided around the discharge chute to control flying debris. French agricultural machinery manufacturer Rousseau SA claims to have invented the mechanical rotary mower in 1962.
In horticulture a rotary mower is usually an integral machine that is either pushed by hand or driven by a riding operator, and used to cut amenity and sports turf. The first successful such machine was developed in Australia in 1952 by the Victa company.