Special plea
Black's Law Dictionary · Henry Campbell Black, M.A. · 1910
Black's Law Dictionary
A special kind of plea in bar, distinguished by this name from the general issue, and consisting usually of some new affirmative matter, though it may also be in the form of a traverse or denial. See Steph. PI.
52, 162; Allen v. New Haven & N. Co., 49 Co.nn. 245.