Definition of "identifier"

identifier

noun
plural identifiers
1. Someone who identifies; a person who establishes the identity of someone or something.
  Quotations
  The Identifier personally inspects each horse in each race by verifying the lip tattoo, body color, head and leg markings, scars, and chestnut (night eyes).
  2001, Theodore A. Landers, The Career Guide to the Horse Industry‎
  The foal papers are documents recording the horse's registration; no horse can start in any race unless his papers are in the hands of the track's identifier.
  2004, John McEvoy, Great Horse Racing Mysteries: True Tales from the Track‎
  Here, we would use the anonymous key technique to obtain a quantum identification protocol AKI of the challenge-response type in which the identifier cannot pretend to be the identifiee […]
  2007, Paolo Tombesi, Osamu Hirota, Quantum Communication, Computing, and Measurement 3, page 291
2. Something that identifies or uniquely points to something or someone else.
  Quotations
  Prehistoric artists used hand-prints in cave paintings, perhaps as a 'signature'. They might be considered the earliest example of a biometric identifier.
  2008, Ted Dunstone, Neil Yager, Biometric System and Data Analysis
3. One who identifies as a particular type or role; one who says and believes that they are a certain thing.
  Quotations
  While the DOJ and BOJS already calculate data by gender, trans identifiers are not included, it is solely by men and women
  2019, Raina Simone Henderson, The Cost of Identity, page 80
4. A guidebook that helps determine the specific class of an object (such as a mushroom, herb, fish, bird, drug, or mineral), or its individual identity (such as that of a star).
5. (programming, operating systems) A formal name used in source code to refer to a variable, function, procedure, package, etc. or in an operating system to refer to a process, user, group, etc.
6. (HTML) A code that distinguishes a particular element from all other elements in a document.
7. (databases) A primary key.