thion- Chem.
(ˈθaɪən)
[a. Gr. θεῖον sulphur: cf. thio-.]
A name for sulphur taking the place of oxygen in a compound and joined by two bonds to carbon.
e.g. in methyl thioncarbamate, H2N.CS.OCH3, as distinct from methyl carbamate and methyl-thiolcarbamate: see thiol-. (Certain words beginning with thion- do not conform to this system: see thionic, etc. under thio-.)
| 1899 [see thiol-]. 1904 Ibid. LXXXVI. i. 990 The crude ester..is best converted directly into thionoxanilic acid, NHPh.CS.CO2H. |