Entry 1 sense Webster, 1913 Gemsbok /gĕm'-zbäk/ · Gems·bok · IPA /ˈɡɛmzˌbɑk/ 01 n. A South African antelope (Oryx Capensis), having long, sharp, nearly straight horns. 1. A South African antelope (Oryx Capensis), having long, sharp, nearly straight horns.(Zool.)