any of three related compounds, including acetone, found in the blood and urine when there is excessive oxidation of fatty acids by the liver, as during starvation or pregnancy, or in diabetes
See ketone body in American Heritage Dictionary 4
noun
A ketone-containing substance, such as acetoacetic acid, that is an intermediate product of fatty acid metabolism. Ketone bodies tend to accumulate in the blood and urine of individuals affected by starvation or uncontrolled diabetes mellitus. Also called acetone body.