A jigsaw is a saw which uses a reciprocating blade to cut irregular curves, such as stenciled designs, in wood, metal, or other materials.

A jigsaw is a sharp power tool that's used for cutting curvy lines in wood or other materials. While most saws can only cut in a straight line, a jigsaw makes it easier to cut complicated patterns and shapes. If you were making a jigsaw puzzle out of wood, you'd use a jigsaw.