Circular saw FIXTEC FCS18501 Circular saw (outdated names: circular saw, circular saw, also the colloquial name for a circular saw: circular saw) is a cutting tool in the form of a flat metal disk, on the outer edge of which there are teeth. It is used on circular saws, pendulum and other machines, as well as in hand-held power tools for cutting various materials, most often wood, plastic, and soft metal.