1. Of or pertaining to sulphur.
2. (Science: chemistry) Derived from, or containing, sulphur; specifically, designating those compounds in which the element has a lower valence as contrasted with the sulphuric compounds. Having the characteristic odour of sulphur dioxide, or of hydrogen sulphide, or of other sulphur compounds. Sulphurous acid. Sulphur dioxide. See Sulphur. 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).
Origin: L. Sulphurosus, sulfurosus: cf. F. Sulfureux. Harsh or corrosive in tone; an acerbic tone piercing otherwise flowery prose; a barrage of acid comments; her acrid remarks make her many enemies; bitter words; blistering criticism; caustic jokes about political assassination, talk-show hosts and medical ethics; a sulfurous denunciation.