Entry 1 sense Webster, 1913 Heliochromy /(hē"lĭ*ō̇*krō`my̆ [or] hē`lĭ*ŏk"rō̇`my̆)/ · He·li·o·chro·my · IPA 01 n. The art of producing photographs in color. 1. The art of producing photographs in color.