international auxiliary language

An international auxiliary language (sometimes acronymized as IAL or contracted as auxlang) is a language meant for communication between people from different nations who do not share a common first language. An auxiliary language is primarily a second language and often a constructed language. The concept is related to but separate from the idea of a lingua franca (or dominant language) that people must use to communicate. The study of international auxiliary languages is interlinguistics.

The term "auxiliary" implies that it is intended to be an additional language for communication between the people of the world, rather than to replace their native languages. Often, the term is used specifically to refer to planned or constructed languages proposed to ease international communication, such as Esperanto, Ido and Interlingua. It usually takes words from widely spoken languages. However, it can also refer to the concept of such a language being determined by international consensus, including even a standardized natural language (e.g., International English), and has also been connected to the project of constructing a universal language.