What is (a) A univalent radical, H.C:O, regarded as the essential residue of formic acid and aldehyde. (b) Formerly, the radical methyl, CH3 called?

formyl — (a) A univalent radical, H.C:O, regarded as the essential residue of formic acid and aldehyde. (b) Formerly, the radical methyl, CH3. (Webster's 1913.)

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