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dialect atlas

American  

noun

Linguistics.
  1. a collection of maps of a certain area indicating the distribution of various phonological, morphological, lexical, or other features of the dialects of that area.


dialect atlas British  

noun

  1. another term for linguistic atlas

"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

Etymology

Origin of dialect atlas

First recorded in 1930–35