The spelling sulfur predominates in United States technical usage, while both sulfur and sulphur are common in general usage. British usage tends to favor sulphur for all applications. The same pattern is seen in most of the words derived from sulfur.
Variants of SULFURIC ACID
sulfuric acid or sul·phu·ric acid\ˌsəl-ˈfyu̇r-ik-\
First Known Use of SULFURIC ACID
Medical Definition of SULFURIC ACID
: a heavy corrosive oily dibasic strong acid H2SO4 that is colorless when pure and is a vigorous oxidizing and dehydrating agent—see oil of vitriol