Kawahori (蝙蝠) is the Japanese word for "bat". The enchantment of blindness likely comes from the misconception that bats are blind (which led to the phrase "blind as a bat"). Bats have decent to poor vision and are not blind; bats rely on echolocation primarily though. A kabuto is a type of helmet in Japan. Thus, Kawahori Kabuto is a "bat helmet".