The following is a Ketone body

Under ceain metabolic conditions associated with a high rate of fatty acid oxidation, liver produces considerable quantities of compounds like acetoacetate and b-OH butyric acid, which pass by diffusion into the blood. Acetoacetate continually undergoes spontaneous decarboxylation to produce acetone. These threesubstances are collectively known as "ketone bodies" (or "acetone bodies"). Sometimes also called as "ketones", which is rather a misnomer Ref: M.N. Chatterjea - Textbook of Biochemistry, 8th edition, page no: 425