{{Unreferenced, date=October 2018 A naturalistic planned language is an ''a posteriori'' constructed language specifically devised to reproduce the commonalities in morphology and vocabulary from a group of closely related languages, usually with the idea that such a language will be easier to use passively – in many cases, without prior study – by speakers of one or more languages in the group. The term most commonly applies to planned languages predominantly based on the

Romance languages The Romance languages, also known as the Latin or Neo-Latin languages, are the languages that are Language family, directly descended from Vulgar Latin. They are the only extant subgroup of the Italic languages, Italic branch of the Indo-E ...

, best known of which are

Interlingue Interlingue (; ISO 639 ''ie'', ''ile''), originally Occidental (), is an international auxiliary language created in 1922 and renamed in 1949. Its creator, Edgar de Wahl, sought to achieve maximal Grammaticality, grammatical regularity and Na ...

(previously known as ''Occidental'') and

Interlingua Interlingua (, ) is an international auxiliary language (IAL) developed between 1937 and 1951 by the American International Auxiliary Language Association (IALA). It is a constructed language of the "naturalistic" variety, whose vocabulary, ...

. Both were designed to serve as

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 ...

s. However, there are also languages intended for speakers of a particular language family (

zonal constructed languages Zonal auxiliary languages, or zonal constructed languages, are constructed languages made to facilitate communication between speakers of a certain group of closely related languages. They form a subgroup of the international auxiliary languages b ...

), including

Pan-Germanic Pan-Germanism ( or '), also occasionally known as Pan-Germanicism, is a pan-nationalism, pan-nationalist political ideology, political idea. Pan-Germanism seeks to unify all ethnic Germans, German-speaking Europe, German-speaking people, and po ...

Pan-Slavic Pan-Slavism, a movement that took shape in the mid-19th century, is the political ideology concerned with promoting integrity and unity for the Slavic people. Its main impact occurred in the Balkans, where non-Slavic empires had ruled the South S ...

and even Pan-

Celtic Celtic, Celtics or Keltic may refer to: Language and ethnicity *pertaining to Celts, a collection of Indo-European peoples in Europe and Anatolia **Celts (modern) *Celtic languages **Proto-Celtic language *Celtic music *Celtic nations Sports Foot ...

naturalistic planned languages. Since the creation of such a language often includes shared idiosyncrasies from the source languages, active use seems to be generally more difficult to learn than for schematic planned languages, though because of grammatical simplification considerably easier than for ethnic languages of the same type.

See also