Mount Miwa was first described in the Kojiki as Mount Mimoro (三諸山). Both names were in common use until the reign of Emperor Yūryaku, after which Miwa was preferred. Mimoro has been held to mean something like august, beautiful (mi) and room, or hall (moro corruption of muro). The current kanji 三 (mi) and 輪 (wa) are purely phonetic. It has also been written 三和, another a phonetic spelling with the same pronunciation.