(záo) chisel; to bore a hole; to chisel or dig; certain; authentic; irrefutable
(zuò) see 鑿|凿[zao2]
(záojǐng) to dig a well
(záozǐ) chisel
(záoruì) to fit like mortise and tenon
(záoshíchǎng) rock quarry
(záokōng) to open an aperture; (extended meaning) to cut a way through; to open up a road