heliochromy

== English == === Etymology === From helio- +‎ chromo- +‎ -y. === Noun === heliochromy (uncountable) (dated or historical) The art of producing colour photographs, especially using a certain, now obsolete, technique. ==== Derived terms ==== heliochrome heliochromic === References === “heliochromy”, in OneLook Dictionary Search. “heliochromy”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.