borer

He was surrounded by armour, treasure, and various implements, including the fire-borer.

The 5⁄8-inch pipe is tapped with the tap borer in the center.

The rockets were slowly cut; the borer jarred at the bottom of its hole; again the disintegrators droned out.

His attention was drawn to the borer, now dimly illuminated by its portable light, which had been secured to the door.

He started slowly around the borer, found a long narrow door slightly ajar, and stepped inside.