1. a mower with multiple blades mounted on a cylinder. The blades cut against a bar. It makes precise cuts and is ideal for lower mowing heights. The blades require professional sharpening. These mowers are safer to use than rotary mowers.
2. A mower that shears the grass between a blade on a spinning reel and a bedknife at the base of the cutting unit. See also Flail mower, Rotary mower, and Triplex.
Source: Ohio State Turf