Search gender: all male female ニジ Japanese Girl Names Variations. 2 names found. gender: all male female Name: niji Katakana: ニジ 0 Kanji: にじ Meaning: に じ Name: niji Katakana: ニジ 0 Kanji: 虹 Meaning: 虹Rainbow. You can save your favorite names with NAZUKE PON > About Japanese Names > Search Japanese Names By Kanji > ニジ Japanese Girl Names Variations.