Samurai Sword is a ridiculous generalisation; there are many types of 'samurai swords'; Shinken, Nodachi, Ōdachi, Chokutō, Katana, Shin guntō, Tachi, Tsurugi, Uchigatana, Kodachi, Wakizashi, Zanbatō, Tantō and Yoroi tōshi
(Just to make it clear, I copied the names for Wikipedia, because I can't spell and have no idea of how to do those 'o's with the line above them.)
Its like calling the capital of Thailand Bangkok (which it isn't called) or saying that every weapon that looks like a Kalashnikov-pattern rifle and AK-47; sure some may be based on the AK-47, but they are unique!
And no, I don't call then ninja stars; shuriken sounds cool so I stick with that.