D defs.my
Entry 1 sense Webster, 1913

Pentathionic

· Pen·ta·thi·on·ic · IPA
01 a. Pertaining to, or designating, an acid of sulphur obtained by leading hydrogen sulphide into a solution of sulphur dioxide; -- so called be…
  1. 1.
    Pertaining to, or designating, an acid of sulphur obtained by leading hydrogen sulphide into a solution of sulphur dioxide; -- so called because it contains five atoms of sulphur.(Chem.)