coulter
n. countablen. a sharp blade or wheel on a plow that cuts into the soil. It makes a vertical cut in front of the main plow blade to help turn the earth over smoothly.
n. a vertical blade or disc attached to the beam of a plough, designed to make a preliminary cut in the turf or soil ahead of the ploughshare.
The farmer checked the coulter for rust before starting the spring plowing.
A sharp coulter is essential for cutting through thick grass roots when breaking new ground for a garden.
The efficiency of the entire plowing operation depends on the precise alignment of the coulter, which ensures a clean furrow wall and reduces the draft required by the tractor.
Primarily used in agricultural and technical contexts; often paired with 'disc' or 'knife' to specify the type.