We put together this page in order to help you with any terms that you may not be familiar with.
It is divided into three categories:
If you can't find the word you are looking for then you can look it up here: Free Online Dictionary
Parts of the blade from wikipedia.

Aikuchi- A type of sword mounting without a tsuba.
Ashi- Lines falling perpendicularly form the hamon towards the cutting edge.
Bizen Zori- A description of the type of curve found particularly in early and middle Kamakura-period blades whereby the bottom part of the blade exhibits a deep curve that staightens out towards the top.
Bohi- A broad groove extending along the shinogi-ji of the blade.
Boshi- That portion of the hamon that turns back to meet the mune at the kissaki section.
Choji- Hamon pattern resembling a row of packed clove buds.
Daisho- A matching pair of swords worn by the samurai.
Fuchi- An oval piece, usually metal, that fits round the blade over the end of the hilt next to the Tsuba.
Gendaito-Modern or contemporary swords made after 1876 or so.
Habaki- is a piece of metal encircling the base of the blade of a Japanese sword. It is used to lock the tsuba in place, and to maintain the weapon in its saya.
Hada- is the grain in the sword produced by the method of hammering and folding the steel during forging.
Hamon- is the visual effect created on the blade by the tempering process. It is the transition between the region of harder steel of the blade edge and the softer steel of the back of the sword. This difference in hardness is the objective of the tempering process; the visual effect is purely a side effect.
Hi- A groove carved alond the length of the sword.
Ishime- The stone-ground effect on metal sword fittings.
Kashira- The pommel of a sword hilt, usually metal or horn.
Katana- is a curved, single-edged sword traditionally used by the samurai.
Kissaki- Point section of a blade.
Kogai- A kind of bodkin carried in a pocket at the side of the scabbard.
Koshi- Lower portion of a blade, just above the hilt.
Koshirae- is the mounting 'worn' by the Japanese sword, when it is being worn by its owner, unlike the shirasaya the sword wears when in storage.
Koto- Swords made before the start of the Keicho era (1596)
Mei- is the signature of the sword smith.
Mekugi- are the pegs which secure the blade in the handle or Tsuka of the sword.
Menuki- is the small metal parts for decoration, under the grip-wrapping, also for better handling. Holds the hilt to the tang.
Nagamaki- A long-bladed, single edged polearm similar to a naginata and used particularly during the Nambokucho and Muromachi period.
Nagasa- is the length of the blade from Mune-machi to the end of the Kissaki.
Naginata- A curved-blade spear, once used by Japanese monks and samurai. It is approximately seven feet in length including the blade.
Nakago- Unseen extension of the blade under the Tsuka; Tang. Many varieties and characteristics. Holds the Mei and Mekigi-ana. It's rust and condition is a vital characteristic in Kantei.
Nihonto- refers to swords that originated in Japan. No reproductions or chinese copies can have the title Nihonto.
Shirasaya- is a plain wooden Japanese blade mount consisting of a saya and tsuka, used when a blade was not expected to see use for some time and needed to be stored.
Tsuba- is usually a round or occasionally squarish guard at the end of the grip of bladed Japanese weapons, like the katana and its various declinations Tanto, Wakizashi, Naginata etc.
Tsuka- Wood handle of the sword covered by Same (ray skin) and Ito.
Wakizashi- The is a traditional Japanese sword with a shoto blade between 30 and 60 cm (12 and 24 inches), with an average of 50 cm (20 inches). It is similar to but shorter than a katana. The wakizashi was usually worn together with the katana by the samurai or swordsmen of feudal Japan.