ˈsəlˌfōn noun
( -s )
Etymology: International Scientific Vocabulary sulf- + -one; probably originally formed as German sulfon
: any of a class of organic compounds that are characterized by the sulfonyl group doubly united by means of its sulfur usually with carbon (as with two hydrocarbon radicals or a single bivalent radical) and that are in general crystalline stable compounds made by oxidation of organic sulfides and in other ways ; especially : diaminodiphenyl sulfone or a derivative or closely related compound used in medicine chiefly in the treatment of leprosy