GNU Collaborative International Dictionary of English

Found one definition

1.       
   Colter (?), n. [AS. culter, fr. L. culter plowshare, knife. Cf. Cutlass.] A knife or cutter, attached to the beam of a plow to cut the sward, in advance of the plowshare and moldboard. [Written also coulter.]
   
   [1913 Webster]