From the Theosophical Glossary by H.P. Blavatsky 1892:
Metatron (Heb.). The Kabbalistic "Prince of Faces", the Intelligence of the First Sephira, and the reputed ruler of Moses. His numeration is 314, the same as the deity title "Shaddai", Almighty. He is also the Angel of the world of Briah, and he who conducted the Israelites through the wilderness, hence, the same as "the Lord God" Jehovah. the name resembles the Greek word metathronon or "beside the throne".