chromogens

/K R OW1 M AH0 JH AH0 N Z/
noun
  1. 1

    Any substance that lacks colour, but can be converted into a pigment or dye.

  2. 2

    A strongly pigmented organelle or organism.

Source: https://en.wiktionary.org/wiki/chromogen, https://en.wiktionary.org/wiki/chromogens