Yama n. : The king of the infernal regions, corresponding to the Greek Pluto, and also the judge of departed souls. In later times he is more exclusively considered the dire judge of all, and the tormentor of the wicked. He is represented as of a green color, with red garments, having a crown on his head, his eyes inflamed, and sitting on a buffalo, with a club and noose in his hands.

Example:
How long should I practice prana-Yama each day?

Taxonomy
King Yama, Naraka, Buddhist, hell, Enma, Dewi, Hinduism, Yu, Chinese mythology, Jigoku, free encyclopedia, twin, myths, soul, character, Yima, Avesta, Yamadipati.

Defination from the web:
Yama belongs to an early stratum of Vedic mythology. In Vedic tradition Yama was considered to have been the first mortal who died and espied the way to the celestial abodes, and in virtue of ... There is a one of a kind temple in Srivanchiyam, Tamil Nadu, India, dedicated to Yama. ...