sulphonium

Century Dictionary and Cyclopedia

1. n. A hypothetical univalent radical,—SH₃. Derivatives in which the hydrogen is replaced by hydrocarbon radicals, such as methyl, CH₃, are known and resemble the corresponding ammonium compounds in constitution and general properties.

Wiktionary

1. n. alternative spelling of sulfonium.

GNU Webster's 1913

1. n. (Chem.) A hypothetical radical, SH3, regarded as the type and nucleus of the sulphines.