The round or occasionally squarish handguard between the handle and the blade of bladed Japanese weapons, like the katana, tachi, wakizashi, tantou, naginata, etc. They contribute to the control of the arm (the right index of the fighter typically touches the tsuba), and they prevent the hand from slipping onto the blade.
The most common shapes of tsuba are round (maru gata), rounded-square (kaku gata) and four lobed (mokko) with many variations within each basic design.
