(bound form) chisel; to bore a hole; to chisel; to dig; (literary) certain; authentic; irrefutable; also pr. [zuo4]

to cut (a canal, tunnel, well etc)

incompatible (abbr. for 方枘圓鑿|方枘圆凿[fang1 rui4 yuan2 zao2]); (literary) compatible (lit. "mortise and tenon")

mortise chisel

to bore a hole; to give a forced interpretation

a forced analogy (idiom); to jump to an unwarranted conclusion

(lit.) like a square peg in a round hole (idiom); (fig.) incompatible

(idiom) to speak with conviction