sulphurous

• POS: Adjective
• HYPHEN: sul=phur=ous

CIDE DICTIONARY

sulphurous, a. [L. sulphurosus, sulfurosus: cf. F. sulfureux.].

•  Of or pertaining to sulphur.  [1913 Webster]
•  Derived from, or containing, sulphur; specifically, designating those compounds in which the element has a lower valence as contrasted with the sulphuric compounds.  [1913 Webster]

Sulphurous acid. (a) Sulphur dioxide. See under Sulphur. [Obs.] (b) An acid, H2SO3, not known in the free state except as a solution of sulphur dioxide in water, but forming a well-known series of salts (the sulphites). -- Sulphurous anhydride (Chem.), sulphur dioxide. See under Sulphur.

OXFORD DICTIONARY

sulphurous, adj. (US sulfurous)
1 relating to or suggestive of sulphur, esp. in colour.
2 Chem. containing quadrivalent sulphur.

Idiom

sulphurous acid an unstable weak acid used as a reducing and bleaching acid.

Etymology

L sulphurosus f. SULPHUR