What does sulfate mean?
A sulfate is a chemical compound derived from sulfuric acid, usually containing the sulfate ion, SO₄²⁻. The word covers a broad family of salts, including copper sulfate, magnesium sulfate, and ferrous sulfate, as well as some organic compounds formed from sulfuric acid. In general writing, “sulfate” most often identifies a substance in chemical, agricultural, industrial, or environmental contexts. It can also be used as a verb for a treatment or conversion involving sulfate compounds. The word is closely related to sulfur and sulfuric acid, and it is distinct from sulfide, which does not contain oxygen. Whether spelled sulfate or the traditionally British sulphate, the term is precise technical vocabulary rather than everyday slang.
A salt containing the sulfate ion, SO₄²⁻, or an ester of sulfuric acid.
"The mineral sample was rich in magnesium sulfate."
This is the most common modern use of the word, especially in chemistry and environmental science.
To treat a substance with a sulfate compound or convert it into a sulfate.
"The manufacturer sulfate-treated the material before dyeing it."
This use is chiefly technical and is less frequent than the noun.
The standard plural is sulfates; the British spelling sulphates is also common.
"The researchers measured the sulfates dissolved in the lake water."
Sulfate gives sulfate-bearing minerals and salts their distinctive chemical identity, from the familiar crystals of copper sulfate to the sulfate minerals abundant in Earth's crust.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does sulfate come from?
The word sulfate was formed in the early 19th century from sulfur, the element from which sulfuric acid is derived, together with the chemical suffix -ate, indicating a salt or compound of an acid. It developed alongside related chemical terms such as sulfide and sulfite. The alternative spelling sulphate reflects a British convention that was historically applied to words containing the combinations sulph- and sulf-.
Related word forms
How sulfate is actually used
The spelling sulfate is standard in American English and widely used in British English; sulphate is also common in British usage. As a verb, sulfate is chiefly technical or industrial and is less common than the noun.
Easily confused with sulfate
A sulfate contains sulfur in its highest common oxidation state with oxygen, whereas a sulfide contains sulfur combined directly with another element and no oxygen.