[al-uh-kruh-mat-ik, -kroh-]
  1. Physical Chemistry. pertaining to or having photochemical properties resulting from an impurity or from exposure to radiation.
  2. Mineralogy. (of a mineral) having no color in itself but bearing colored impurities.
Compare idiochromatic.

Origin of allochromatic

First recorded in 1875–80; allo- + chromatic Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018