What is a machine for grinding or commuting any substance, as grain, by rubbing and crushing it between two hard, rough, or intented surfaces; as, a gristmill, a coffee mill; a bone mill called?

mill — A machine for grinding or commuting any substance, as grain, by rubbing and crushing it between two hard, rough, or intented surfaces; as, a gristmill, a coffee mill; a bone mill. (Webster's 1913.)

Sources