thiotoluidine noun1 •Diamidoditolyl sulphide, (C₇H₆ּ·NH₂)₂S, a substance used in the production of some azo dyes.If the amount of sulphur be doubled, thiotoluidine is almost absent, the product containing, together with dehydrothiotoluidine, a more highly condensed base […] — 1889
