A tap is designed so that the pollution of the environment can be prevented and the cleaning can be simplified. The tap includes an intake hole having openings at a screw portion of the tap. Air intake is performed through the intake hole, so that the chips generated by the screw portion in the cutting can be aspirated from the openings forcibly. Because the chips can be discharged without using cutting fluids, pollution of the environment can be prevented. Because the chips can be aspirated from the openings and discharged from the intake hole of the tap, the chips are not scattered on the work piece, and thus a cleaning process of the work piece can be simplified.