Language contactLanguage contact occurs when speakers of two or more languages or varieties interact with and influence each other. The study of language contact is called contact linguistics. When speakers of different languages interact closely, it is typical for their languages to influence each other. Language contact can occur at language borders, between adstratum languages, or as the result of migration, with an intrusive language acting as either a superstratum or a substratum.
Dialect continuumA dialect continuum or dialect chain is a series of language varieties spoken across some geographical area such that neighboring varieties are mutually intelligible, but the differences accumulate over distance so that widely separated varieties may not be. This is a typical occurrence with widely spread languages and language families around the world, when these languages did not spread recently.
DialectDialect (from Latin dialectus, dialectos, from the Ancient Greek word διάλεκτος, 'discourse', from διά, 'through' and λέγω, 'I speak') can refer to two distinctly different types of linguistic phenomena. One usage refers to a variety of a language that is a characteristic of a particular group of the language's speakers. Under this definition, the dialects or varieties of a particular language are closely related and, despite their differences, are most often largely mutually intelligible, especially if geographically close to one another in a dialect continuum.
