acid radical

noun

1

: the negative ion (as the sulfate ion SO₄⁻⁻) of an acid : anion

—now used especially by analysts

2

: a radical formed by removal of all hydroxyl or analogous groups (as mercapto) from an acid

benzoyl C₆H₅CO− is the acid radical corresponding to benzoic acid C₆H₅COOH

sulfuryl >SO₂ is the acid radical of sulfuric acid H₂SO₄

compare acyl

Word History

First Known Use

1788, in the meaning defined at sense 1

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