'Lower Sonoran' definitions:

Definition of 'Lower Sonoran'

From: GCIDE
  • Sonoran \So*no"ran\, a. (Biogeography) Pertaining to or designating the arid division of the Austral zone, including the warmer parts of the western United States and central Mexico. It is divided into the
  • Upper Sonoran, which lies next to the Transition zone, and the
  • Lower Sonoran, next to the Tropical. [Webster 1913 Suppl.]