Shigeo Sugawa has a web site both in English and Japanese which is well worth taking some time to browse through, he has info on all types of Japanese firearms and other weapons etc. Shigeo is the author of "The Japanese matchlock:The Story of the Tanegashima"
Below is the must complete glossary of Japanese matchlock terms that I know of.
http://www.xn--u9j370humdba539qcybpym.jp/
http://www.japaneseweapons.net/