Bahamut, or Bahamoot, according to Zakariya al-Qazwini, is a monster that lies deep below, underpinning the support structure that holds up the earth.
The fish (Bahamut) carries on its back the giant bull (Kuyuta), and on the green hyacinth slab stands an earth-bearing angel.—Surüri's Turkish translation of al-Qazwini. Topkapi Palace Museum, Istanbul, MSSA A 3632, folio 131a
Kuyūthā is the cosmic bull in medieval Islamic cosmography. It is said to carry on its back the angel who shoulders the earth and the rock platform upon which the angel stands. The bull is said to stand on the giant fish or whale, Bahamut.
The cosmic bull bears the earth-disk (rimmed by Mount Qaf) and stands on the fish (Bahamut). Islamic cosmography.—Zekeriya Kazvinî, Acaib-ül Mahlûkat (The Wonders of Creation), in Turkish from the Arabic of al-Qazwini. c.1553
The angel-supporting ruby mountain ("montagne de rubis") balanced on the multi-horned bull. Islamic cosmography.—Gentil Album (1774), p. 34. Held by the Victoria and Albert Museum.