amphichroic

from The Collaborative International Dictionary of English v.0.48

Amphichroic \Am`phi*chro"ic\, a. [Gr. 'amfi` + ? color.] (Chem.)
   Exhibiting or producing two colors, as substances which in
   the color test may change red litmus to blue and blue litmus
   to red.
   [1913 Webster] Amphicoelian