COULTER

[coul.ter] n [ME colter, fr. OE culter & OF coltre, both fr. L culter plowshare; akin to Gk skallein to hoe--more at shell] (bef. 12c): a cutting tool (as a knife or sharp disc) that is attached to the beam of a plow, makes a vertical cut in the surface, and permits clean separation and effective covering of the soil and materials being turned under