tiānzǐ
前世修中品下品之十善生於人中為國王者，為諸天所護持，故名天子。仁王經上曰：「十善菩薩發大心，長別三界苦輪海，中下品善粟散王，上品十善鐵輪王。」金光明經三曰：「雖在人中生為人王，以天護故復稱天子。」 欲界第六天之主曰天子，如天子魔是也。
A son of Heaven. The Emperor-Princes, i. e. those who in previous incarnations have kept the middle and lower grades of the ten good qualities 十善 and, in consequence, are born here as princes. It is the title of one of the four mara, who is 天主 or lord of the sixth heaven of desire; he is also known as 天子魔 (天子業魔) and with his following opposes the Buddha-truth.
the rightful Emperor; the Son of Heaven
一天子 (一)謂於人中為王，而蒙諸天護持者。此乃前世修中、下品之十善所得之果報。金光明經卷三（大一六‧三四七上）：「雖在人中，生為人王，以天護故，復稱天子。」 (二)指欲界第六天之魔王，即他化自在天子魔。 (三)指諸天之天人。p1732