n. 25B6; noun he drives like a lunatic : MANIAC, madman, madwoman, imbecile, psychopath, psychotic; fool, idiot; eccentric; informal loony, nut, nutcase, head case, psycho, moron; Brit. informal nutter; N. Amer. informal screwball.
25B6; adjective
a lunatic prisoner. : See mad sense 1.
a lunatic idea. : See mad sense 3.