\Sul"phur*yl\, n. [Sulphur + -yl.] (Chem.)
The hypothetical radical {SO2}; -- called also {sulphon}.
{Sulphuryl chloride}, a chloride, pungent, fuming liquid,
   {SO2.Cl2}, obtained by the action of phosphorus
   pentachloride on sulphur trioxide. On treatment with water
   it decomposes into sulphuric and hydrochloric acids, and
   is hence called also {sulphuric chloranhydride}.