sulf·am·ide \ˌsəlˈfaˌmīd, ˈsəlfəˌm-, -_mə̇d\noun Etymology: International Scientific Vocabulary sulf- + amide 1. a.: a crystalline neutral compound SO2(NH2)2 obtainable by treating sulfuryl chloride with ammonia : the amide of sulfuric acid b.: any of several derivatives of this compound 2.: sulfonamide