Word Study
carbonyl
CIDE DICTIONARY
carbonyl, n. [Carbon + -yl.].
The radical (CO)′′ , occuring, always combined, in many compounds, as the aldehydes, the ketones, urea, carbonyl chloride, etc. [1913 Webster]
" Though denoted by a formula identical with that of carbon monoxide, it is chemically distinct, as carbon seems to be divalent in carbon monoxide, but tetravalent in carbonyl compounds." [1913 Webster]
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