日本人によると刀は刀かもしれませんが、外国人にとっては、日本の剣と別の国の剣や剣の種類を区別したいです。だから、「samurai(侍)」と付けています。
刀をお土産に買いたい外国人が多いので、売っているお店に連れて行ってあげようと思うのです。
Since there are a lot of foreigners who want to buy samurai swords as souvenirs, I'm thinking of going along with them to a store that sells them.
The word "katana" is very commonly known around the world so if you were to use it, most people would understand you. If not, the phrase "Japanese samurai sword" should help your listener to understand exactly what type of sword you are talking about. I hope that this helps. :)
The Katana is often referred to as a 'Samurai Sword' in western culture, and is depicted in many movies as such.
The Katana is a traditional Japanese weapon used before the introduction of firearms and after also. Tourists try to take these weapons as souvenirs or gifts to their native country, but because of the lethality of these swords many countries have banned the importation of them.
Alot of people would actually know what a 'Katana' but if not then you would explain it's a 'samurai sword' you could also call it a 'Japanese sword' or a 'Japanese samurai sword'
tradiitonal means it has been around for a long time or is part of a countries tradition
アメリカ合衆国 
イギリス 
日本 
