Acetone is a colorless, volatile, flammable and water-soluble liquid. It is typically used for cleaning purposes, and as a solvent for other materials such as plastics, synthetic fibers, paints and varnishes. Common uses for acetone also include thinning paint. You probably heard of acetone as the main active ingredient in nail polish remover. It also works great as adhesive remover. Finally you can also use it as a heavy-duty degreaser.