An insane person, particularly one suffering from mania in any of its forms. Said to be inapplicable to Idiots (Com. v. Haskell, 2 Brewst. [Pa.] 497); but it is not a technical term either of medicine or the law, and is incapable of being applied with scientific precision. See Insanity.
MADMAN
TheLaw.com Law Dictionary & Black's Law Dictionary 2nd Ed.