Language border

Geolinguistic boundary between mutually intelligible speech communities

A language border or language boundary is the line separating two language areas. The term is generally meant to imply a lack of mutual intelligibility between the two languages. If two adjacent languages or dialects are mutually intelligible, no firm border will develop, because the two languages can continually exchange linguistic inventions; this is known as a dialect continuum. A "language island" is a language area that is completely surrounded by a language border.

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