“Rulai” was translated form the Sanskrit word “Tathagata”. “Ru” means “suchness”(tathata), or “according to the reality”(Yathabhutam), i.e. the ultimate reality of all dhammas, while “lai” means “come”. “Rulai”(Tathagata) is interpreted in the Buddhist scriptures as “coming by the path of Tathagata” or “coming according to the reality”. Tathagata is a general term and another name for “the Buddha”. Thus Gotama Buddha can be called Gotama Tathagata, and Amita Buddha can be called Amita Tathagata. (From Essentials of Buddhism: Questions and Answers)