heliochromy

From helio- +‎ chromo- +‎ -y.

heliochromy (uncountable)

1. (dated or historical) The art of producing colour photographs, especially using a certain, now obsolete, technique.

• heliochrome
• heliochromic

• “heliochromy”, in OneLook Dictionary Search.
• “heliochromy”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.