刀 - sword, saber, knife

Japanese sword (usu. single-edged and curved); Japanese bladed weapon

sword; dagger; knife; bayonet

sword (esp. Japanese single-edged); katana

(Japanese) long sword; large sword

razor

(small) knife

long sword (as opposed to the shorter katana)

short sword; knife; dagger; dirk; tantō

bamboo sword (for kendo); bamboo fencing stick

Pacific saury is only good if it's from Meguro

dagger; stiletto

performing a surgical operation