What is "eisai"

was a Japanese Buddhist priest, credited with bringing both the Rinzai school of Zen Buddhism and green tea from China to Japan. He is often known simply as Eisai/Yōsai Zenji (栄西禅師), literally "Zen master Eisai".

is a Japanese pharmaceutical company headquartered in Tokyo, Japan. It has some 10,000 employees, among them about 1,500 in research. Eisai is listed on the Tokyo Stock Exchange and is a member of the Topix 100 and Nikkei 225 stock indices.