Define vocabularies with terms defined in a single language, usually English
Vocabularies with a global scope maintain their terms in a single language, usually English.
In other domains, users can define their own vocabularies in a local language to facilitate the development of ontologies by domain experts
Most popular vocabularies and ontologies for the semantic web (FOAF, Dublin Core, OWL, RDF Schema, etc.) are monolingual and only employ one language, English, both for labels and comments.
In monolingual vocabularies, it is easy to control the vocabulary evolution and avoid the appearance of bad translations or ambiguities between language versions.
When using monolingual vocabularies in a multilingual application, it is necessary to have a translation layer for those English terms.
Using a monolingual vocabulary as the central knowledge representation system can be constrained by the language used. For example, some languages have different names for one concept that refer to only one name in another language.
Also, some concepts in one language might not exactly match to a concept in another language.
An example is the concept Professor, which in certain regions refers only to an academic holding a chair at a university (e.g. Germany), while it comprises in other regions also secondary or even primary school teachers (such as in Austria).
This example illustrates, that such ambiguities can even occur in largely monolingual vocabularies, where the meaning of concepts differs in various regions.
This pattern is opposed to the Multilingual vocabularies pattern.
Most of these vocabularies use descriptive URIs pattern with English terms.