Ke"tone (kē"tōn), 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.

&fist; 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.

• (chemistry) Any of a large class or organic compounds (R1.CO.R2) having a carbonyl functional group attached to two hydrocarbon radicals