EL SHADDAI, EL SHADDAY ĕl shăd’ ī (אֵ֣ל שַׁדַּ֔י, God of the mountain(s) or God Almighty). An epithet of God in the patriarchal narratives and as an archaism in many poetic passages of the OT.
See Names of God.
W. F. Albright, From the Stone Age to Christianity, 2nd ed. (1957), 15, 243, 244n., 247, 271, 300.