What is "radial arm saw"

n. A circular saw mounted to slide along a horizontal beam

A radial arm saw is a cutting machine consisting of a circular saw mounted on a sliding horizontal arm. Invented by Raymond DeWalt in 1922, the radial arm saw was the primary tool used for cutting long pieces of stock to length until the introduction of the power miter saw in the 1970s.

In addition to making length cuts, a radial arm saw may be configured with a dado blade to create cuts for dado, rabbet or half lap joints. In addition some radial arm saws allow the blade to be turned parallel to the back fence, allowing a rip cut to be performed.