In linguistics

Linguistics

Linguistics is the scientific study of human language. Linguistics can be broadly broken into three categories or subfields of study: language form, language meaning, and language in context....

, code-switching is the concurrent use of more than one language

Language

Language may refer either to the specifically human capacity for acquiring and using complex systems of communication, or to a specific instance of such a system of complex communication...

, or language variety

Variety (linguistics)

In sociolinguistics a variety, also called a lect, is a specific form of a language or language cluster. This may include languages, dialects, accents, registers, styles or other sociolinguistic variation, as well as the standard variety itself...

, in conversation. Multilinguals

Multilingualism

Multilingualism is the act of using, or promoting the use of, multiple languages, either by an individual speaker or by a community of speakers. Multilingual speakers outnumber monolingual speakers in the world's population. Multilingualism is becoming a social phenomenon governed by the needs of...

—people who speak more than one language—sometimes use elements of multiple languages in conversing with each other. Thus, code-switching is the use of more than one linguistic variety in a manner consistent with the syntax

Syntax

In linguistics, syntax is the study of the principles and rules for constructing phrases and sentences in natural languages....

 and phonology

Phonology

Phonology is, broadly speaking, the subdiscipline of linguistics concerned with the sounds of language. That is, it is the systematic use of sound to encode meaning in any spoken human language, or the field of linguistics studying this use...

 of each variety.

Code-switching is distinct from other language contact

Language contact

Language contact occurs when two or more languages or varieties interact. The study of language contact is called contact linguistics.Multilingualism has likely been common throughout much of human history, and today most people in the world are multilingual...

 phenomena, such as borrowing

Loanword

A loanword is a word borrowed from a donor language and incorporated into a recipient language. By contrast, a calque or loan translation is a related concept where the meaning or idiom is borrowed rather than the lexical item itself. The word loanword is itself a calque of the German Lehnwort,...

, pidgin

Pidgin

A pidgin , or pidgin language, is a simplified language that develops as a means of communication between two or more groups that do not have a language in common. It is most commonly employed in situations such as trade, or where both groups speak languages different from the language of the...

s and creoles

Creole language

A creole language, or simply a creole, is a stable natural language developed from the mixing of parent languages; creoles differ from pidgins in that they have been nativized by children as their primary language, making them have features of natural languages that are normally missing from...

, loan translation (calques)

Calque

In linguistics, a calque or loan translation is a word or phrase borrowed from another language by literal, word-for-word or root-for-root translation.-Calque:...

, and language transfer (language interference).