Entry 2 senses Webster, 1913 Mad-apple · Mad·-ap·ple · IPA 01 n. The eggplant bush (Solanum melongena). See Eggplant. 1. The eggplant bush (Solanum melongena). See Eggplant.(Bot.) See: Eggplant 2. The fruit of the eggplant bush, a large egg-shaped vegetable having a shiny skin typically dark purple but occasionally white or yellow. Syn. eggplant, aubergine, brinjal, eggplant bush, garden egg, Solanum melongena. — Syn. -- eggplant, aubergine.