(1) A sequence of bits or characters that identifies a user, program, device, or system to another user, program, device, or system. See also data name.
(2) In the C language, a sequence of letters, digits, and underscores used to identify a data object or function.
(3) In COBOL, a data name that is unique or is made unique by the correct combination of qualifiers, subscripts, or indexes.
(4) In the 3270 terminal services development tool, a field on a screen definition that uniquely identifies the state of the screen. Users can choose which fields will be identifiers when creating recognition profiles.
(5) The name of an item in a program written in the Java language.
(6) One or more characters used to identify or name a data element and possibly to indicate certain properties of that data element.