An approximate equivalence of a translation unit will be used if there is no exact equivalence, i.e. culture-specific terms or terms from the area of public administration.

For example, the Spanish tarjeta sanitaria ('healthcare card') or empadronamiento ('registration at the town hall') have no equivalent in many of the languages as well as many other concepts that denote specific concepts that do not exist in the other language. In this case is sometimes possible to use an 'approximate' equivalence, sometimes called 'translation equivalence', or 'cultural equivalent', i.e. a term that denotes a closely related concept.