Terunoumi Masato, also known as Daikiko Masato, born Masato Hayashi (September 15, 1967 – June 6, 2009), was a sumo wrestler from Gobo, Wakayama, Japan.
A former amateur champion, he made his professional debut in 1990.
His highest rank was maegashira 15.
He was the first wrestler in the six tournaments per year era to reach the top makuuchi division after spending just one tournament in the second highest juryo division.
After injury problems he retired in 1993, and died at the age of 41 in 2009.