Word Study
hydroxy-
CIDE DICTIONARY
hydroxy-,
A combining form, also used adjectively, indicating hydroxyl as an ingredient. [1913 Webster]
Hydroxy acid (Chem.), an organic acid, having (besides the hydroxyl group of the carboxyl radical) an alcoholic hydroxyl group, and thus having the qualities of an alcohol in addition to its acid properties; as, lactic and tartaric acids are hydroxy acids.
OXFORD DICTIONARY
hydroxy-, comb. form Chem. having a hydroxide ion (or ions) or a hydroxyl group (or groups) (hydroxybenzoic acid).
Etymology
HYDROGEN + OXYGEN
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