The invention relates to a knife of a lawnmower. The knife has at least two blade wings (2) arranged around the vertical axis (1), the blade wings (2) in the radial direction (19) on the outside each having a cutting edge section (3) with a blade depth (TF), with a leading sharpened cutting edge (4) and with a trailing trailing edge (5). The cutting section (3), viewed in the cross section of the blade blade (2), has a contour (21) which extends from the cutting edge (4) and runs to the trailing edge (5) in the usual installation position. The upper contour (21), starting from the cutting edge (4) over at least half of the chord depth (TF), is determined by an upper curve (22), the upper curve (22) being curved in a curve and at least partially convex toward the trailing edge (5) ) increases. The upper curve (22) extends at the location of the cutting edge (4) at an entrance angle (±) to the cutting direction (20), wherein the entry angle (±) is in a range of 0 ° inclusive to 5 ° inclusive.