thionic

from The American Heritage® Dictionary of the English Language, 5th Edition.

• adjective Of, relating to, containing, or derived from sulfur.

from The Century Dictionary.

• Of or pertaining to sulphur: used specifically, in chemistry, to indicate that in the molecule of the original substance oxygen has been replaced by sulphur.

from the GNU version of the Collaborative International Dictionary of English.

• adjective (Chem.) Of or pertaining to sulphur; containing or resembling sulphur; specifically, designating certain of the thio compounds. Cf. dithionic, trithionic, tetrathionic, etc.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• adjective Of or pertaining to sulfur