Ei·kon'o·gen noun [ Greek e'ikw`n , e'iko`nos , image + root of gi`gnesqai to be born.] (Photog. & Chem.) The sodium salt of a sulphonic acid of a naphthol, C 10 H 5 (OH)(NH 2 )SO 3 Na used as a developer. Found on http://www.encyclo.co.uk/webster/E/14