File this under “huh.” Ever wondered what “Pikachu” actually means? Sure, you have! “Pika” is from pikapika, which means to sparkle or glitter. “Chu” is from chuchu, the Japanese word for the sound mice make. So put them together, and you get “Pikachu,” AKA “Sparkle Mouse Noise.” A shame the localizers stuck with the Japanese original. We quite like that Sparkle Mouse Noise moniker.
Pikachu’s Meaning [LongCountdown via Japundit][Geek on Stun]