Hamon: border between the tempered cutting edge of a blade and the untempered part of the rest of the sword.
Koiguchi: opening of the Saya.
Kojiri: end piece on the Saya; it's called Sayajiri as well.
Kurigata: Knob on the Omote side of the Saya with a hole for the Sageo to go through.
Mekugi-Ana: hole for the Mekugi.
Mekugis: bamboo (usally) pegs used to secure Tsuka to Nakago.
Menuki: decorative metal pieces fitted on the Tsuba to improve grip on the sword.
Nagasa: blade lenght.
Nakago: tang, unseen extension of the blade under the Tsuka.
Sageo: cord, usually made of silk, attached to the Kurikata of the Saya.
Samé:the belly portion of stingray skin used on top of the wooden Tsuka and below the Ito to improve grip.
Saya: scabbard for the sword.
Seppa: a pair of brass (usually) washers around the Tsuba, between the handle and the blade.
Shitodome: brass (usaully) pieces that fit into the Kashira before the handle is wrapped.
Tsuba: hand guard for a sword, different kinds of decoration.
Tsuka: handle of the sword
Tsuka-Ito: cotton or silk braid used to wrap the Tsuka.