Word Study
hydroxyl
CIDE DICTIONARY
hydroxyl, n. [Hydro-, 2 + oxygen + -yl.].
A compound radical, or unsaturated group, HO , consisting of one atom of hydrogen and one of oxygen. It is a characteristic part of the hydrates, the alcohols, the oxygen acids, etc. [1913 Webster]
OXFORD DICTIONARY
hydroxyl, n. Chem. the univalent group containing hydrogen and oxygen, as -OH.
Etymology
HYDROGEN + OXYGEN + -YL
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