OK, first off:white people love saying “侍”. Usually Japanese use “武士” – which means not only “a warrior” but is also used to refer to the spiritual or social class, as in “武士精神” (samruai spirit) or “武士道” (the philosophy of the samurai). The only time actual Japanese say “侍” is when they’re referring to something very concrete things like “samurai haircut” or “Samurai TV drama.”