What is "yujeong"

Samyeongdang (1544–1610), also known by his dharma name Yujeong, was a Korean Buddhist monk during the Joseon era. He is sometimes identified by his pen name, Song-un. He was born to a family of the Im clan in Miryang, Gyeongsang Province. After the deaths of his mother in 1558 and his father in 1559, he became a monk at Jikjisa on Hwangaksan in Gimcheon.