Identifier
From Computer History Wiki
An identifier is a sequence (often of a fixed, pre-determined length) of bits which designates or selects one particular object of a group of such objects. For instance, an address is an 'identifier' for one particular byte/word in main memory. The term name is often used for the same thing; the two are almost synonyms, except that there is less of an implication that it has a fixed, pre-determined length.
