coss, n. [Cf. Pers. k a road measure of about two miles; or Skr. kr.].
A Hindoo measure of distance, varying from one and a half to two English miles. Whitworth. [1913 Webster]
coss, n. [It. cosa.].
Rule of Coss, an old name for Algebra. [It. regola di cosa rule of thing, the unknown quantity being called the cosa, or the thing.]