光
hikari
/ˈhi.ka.ɾi/
Definition
Light; the brightness that comes from the sun, a lamp, or another source and allows us to see things.
Example
朝の光が部屋に差し込んできた。
The morning light streamed into the room.
Etymology
From Old Japanese *pikari*, the nominalized form of the verb 光る (hikaru, "to shine, to gleam"). The root is reconstructed as Proto-Japonic *pika-, related to the mimetic base *pika* (a flash of light), which survives today in the onomatopoeia ぴかぴか (pikapika, "sparkling, gleaming").
Cultural note
光 (hikari) carries deep cultural weight in Japanese. It is a common given name, a literary symbol of hope and divinity (the legendary prince Hikaru Genji in *The Tale of Genji* is named for his radiant beauty), and the brand name of Japan's famous Shinkansen bullet train line connecting Tokyo and Osaka. In Buddhist contexts, light (光明, kōmyō) symbolizes enlightenment and the compassion of Amida Buddha.