home l Jackson Eaton lightning light⋅ning   [lahyt-ning] –noun 1. a brilliant electric spark discharge in the atmosphere, occurring within a thundercloud, between clouds, or between a cloud and the ground. –verb (used without object) 2. to emit a flash or flashes of lightning (often used impersonally with it as subject): If it starts to lightning, we'd better go inside. –adjective 3. of, pertaining to, or resembling lightning, especially in regard to speed of movement: lightning flashes; lightning speed. a b c d e f g h i j k l m n o p q r s t u v w x y z light-meter lightning litter line loose lolita lonely lost love lounge living-room