sulfate n.

also sulphur, c. 1300, from Anglo-French sulfere, Old French soufre "sulfur, fire and brimstone, hellfire" (13c.), later also sulphur, from Late Latin sulfur, from Latin sulphur, probably from a root meaning "to burn." Ousted native brimstone and cognate Old English swefl, German schwefel, Swedish swafel, Dutch zwavel. The spelling with -ph- is standard in Britain, but its suggestion of a Greek origin is misleading.

in chemistry, word-forming element used to form the names of salts from acids in -ic; from Latin -atus, -atum, suffix used in forming adjectives and thence nouns; identical with -ate (1).

The substance formed, for example, by the action of acetic acid (vinegar) on lead was described in the 18th century as plumbum acetatum, i.e. acetated lead. Acetatum was then taken as a noun meaning "the acetated (product)," i.e. acetate. [W.E. Flood, "The Origins of Chemical Names," London, 1963]