CO

Ketone Ke"tone (k[=e]"t[=o]n), n. [Cf. {Acetone}.] (Chem.) One of a large class of organic substances resembling the aldehydes, obtained by the distillation of certain salts of organic acids and consisting of carbonyl ({CO}) united with two hydrocarbon radicals. In general the ketones are colorless volatile liquids having a pungent ethereal odor. [1913 Webster]

Note: The ketones are named by adding the suffix-one to the stems of the organic acids from which they are respectively derived; thus, acetic acid gives acetone; butyric acid, butyrone, etc. [1913 Webster]