biˈaxal,a. = next. biaˈxality, biaxial character. 1837Whewell Hist. Induct. Sc. (1857) II. 296 Its crystalline symmetry is biaxal.1869Tyndall Notes Light §423 Biaxal crystals, or those which possess two optic axes.1864Reader 85. 206/2 The biaxality ascribed to it.