开刀

开刀	kāi dāo	(of a surgeon) to perform an operation / (of a patient) to have an operation / to decapitate / to behead / to single out as a point of attack
开	kāi	to open (transitive or intransitive) / (of ships, vehicles, troops etc) to start / to turn on; to put in operation; to operate; to run / to boil / to write out (a prescription, check, invoice etc) / (directional complement) away; off / carat (gold) / abbr. for Kelvin, 开尔文 / abbr. for 开本, book format
刀	Dāo	surname Dao
刀	dāo	knife; blade; single-edged sword; cutlass (CL:把) / (slang) (loanword) dollar / classifier for sets of one hundred sheets (of paper) / classifier for knife cuts or stabs / (Internet slang) to bargain; to ask for a small discount (esp. on second-hand marketplaces)