An auxiliary language is a language that is not the primary or native language of a community. It may refer to:
Interlanguage, an idiolect that has been developed by a learner of a second language International auxiliary language, a planned language constructed for international communication, such as Esperanto or International Sign Zonal auxiliary language, a planned language focused on one particular region, often blending elements of somewhat related languages in that region Minority language, a secondary language that has official recognition Sacred language, also called liturgical language or initiation language, used in religious services Lingua franca, a language used to facilitate communication between groups without a common native language
See also International Auxiliary Language Association Secret language (disambiguation)