Search gender: all male female Kuju Boy Name Meaning, Kanji Variations. 1 names found. gender: all male female Name: kuju Katakana: クウジュ 0 Kanji: 空樹 Meaning: 空Sky. Atmosphere. Heaven. Big. Wide. Empty. No substance. Meaningless. Useless. In Buddhism, something without substance or essence. A thing related to aviation. 樹Trees. General term for plants. To plant a tree. To set up. To stand firmly. You can save your favorite names with NAZUKE PON > About Japanese Names > Search For Japanese Names > Kuju Boy Name Meaning, Kanji Variations.