A linking element used to identify a relation between an initialism and its full or expanded form.

ISO12620

The identification of a term relation between an initialism and its full form enables a termbase designer to indicate in a machine-readable way which of several possible synonyms appearing in a terminological entry comprises the base form on which the initialism is created and vice versa. Ordinarily, both terms will appear in the same language section, although this is not necessarily mandatory. In many special languages, for instance in the terminology associated with the World Wide Web, English initialisms are commonly used in other languages, but the English full form is avoided in favor of a translated or other equivalent full form in the language in question. Hence it could occur that an initialism cited in a language B is accompanied by a link pointing to the English language full form.