Definitions for "Tiamat"
(Sumerian Nammu; Canaanite Yahm-Nahar; Biblical Leviathan, Rehab, tehom, tohu; Greek Typhoeus; Hurrian/Hittite Illugankas; Greek Typheous; Roman Typhon) A multi-headed dragon that is killed by Marduk (or Ashur) to save the gods and man kind
Tiamat is a primeval goddess in Babylonian and Sumerian mythology, and a central figure in the Enûma Elish creation epic. John C. L. Gibson, in the Ugaritic glossary of Canaanite Myths and Legends, notes that "tehom" appears in the Ugaritic texts, c. 1400–1200 BCE, simply meaning the "sea". Such a depersonalized Tiamat (the -at ending makes her feminine) is "The Deep" (Hebrew tehom), present at the beginning of the book of Genesis.
(Akkadian) mother of the gods and consort of Apsu
Tiamat is a band from Sweden that was formed in Stockholm, in 1988. Their music can generally be considered doom metal, but the actual classification of the style varies with each album.