The name of an object or concept in a database. An identifier may be the object’s actual name (e.g. ‘London’ or ‘W1 1AA’, a London postcode), or a word describing the concept (‘population’), or an arbitrary identifier such as ‘XY123’ that makes sense only in the context of the particular dataset. Careful choice of identifiers using relevant standards can facilitate data integration.

Source: ODH.

First letter
i