What is "butteris"

Butteris \But"ter*is\, n. [The same word as buttress, noun, in a different application, F. bouter to push.] (Far.) A steel cutting instrument, with a long bent shank set in a handle which rests against the shoulder of the operator. It is operated by a thrust movement, and used in paring the hoofs of horses.

n. (context farriery English) A cutting instrument, with a long bent shank set in a handle which rests against the operator's shoulder, used in pare the hoofs of horses.