Word Study
carboxyl
CIDE DICTIONARY
carboxyl, n. [Carbon + oxygen + -yl.].
The complex radical, CO.OH , regarded as the essential and characteristic constituent which all oxygen acids of carbon (as formic, acetic, benzoic acids, etc.) have in common; -- called also oxatyl . [1913 Webster]
OXFORD DICTIONARY
carboxyl, n. Chem. the univalent acid radical (-COOH), present in most organic acids.
Derivative
carboxylic adj.
Etymology
CARBON + OXYGEN + -YL
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