DÉET (DÉET). - Archaic Egyptian form (d.t.; Coptic tē) denoting the underworld. In primitive times the Egyptians, seeing the stars rise and set at such distant points of the earth, thought that beneath it there was a narrow circular gallery for their passage.
This idea changed when a boat was attributed to the sun and it was thought that at night it crossed this gallery. The river is also called d. But since the d. was also regarded as the dwelling-place of the dead, from the XVIII dynasty onward the Libro di ciò che è nel d. (improperly called Am-Duat) provides an illustrated guide to the twelve regions through which the solar boat travelled at night. Their names, their dimensions, their inhabitants, and the various crews had to be known by the deceased for his spiritual benefit.