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definitions

diglossia

[dahy-glos-ee-uh, -glaw-see-uh]
noun
  1. the widespread existence within a society of sharply divergent formal and informal varieties of a language each used in different social contexts or for performing different functions, as the existence of Katharevusa and Demotic in modern Greece.
  2. Pathology. the presence of two tongues or of a single tongue divided into two parts by a cleft.

Origin of diglossia

1955–60; Latinization of French diglossie, equivalent to Greek díglōss(os) speaking two languages (see diglot) + French -ie -y3
Related formsdi·glos·sic [dahy-glos-ik] /daɪˈglɒs ɪk/, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for diglossia

diglossia

noun
  1. linguistics the existence in a language of a high, or socially prestigious, and a low, or everyday, form, as German and Swiss German in Switzerland

Word Origin for diglossia

C20: New Latin, via French, from Greek diglōssos speaking two languages: see diglot
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
diglossia in Medicine

diglossia

[dī-glŏs′ē-ə]
n.
  1. bifid tongue
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.