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acid radical

noun

Definition of acid radical

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

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First Known Use of acid radical

1788

in the meaning defined at sense 1

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