a level area, as a dry lake bed, in which evaporation has concentrated alkali minerals, as sodium sulfates and carbonates.
Compare salt flat.
Origin of alkali flat
An Americanism dating back to 1870–75
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for alkali flat
an arid plain encrusted with alkaline salts derived from the streams draining into it
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012