English Reference
Noun

identifier

n. countable
B2 Upper Intermediate US /aɪˈdɛntəˌfaɪɝ/ UK /aɪdˈɛntɪfˌaɪə/ iden·ti·fi·er UK spelling identifiers Programming

n.a unique name or label used to recognize a specific person or thing. In computing, it is the name you give to a variable or a piece of data.

n.a sequence of characters used to uniquely distinguish an entity within a specific system or context. In programming, it refers to the user-defined name of a variable, function, or class.


SIMPLE

Each user has a unique identifier in the database.

CONTEXTUAL

The compiler threw an error because the identifier started with a number, which violates the language's naming rules.

COMPLEX

To maintain data integrity across the distributed system, the architecture assigns a globally unique identifier to every transaction, ensuring no two records can ever be confused during synchronization.

Usage

Commonly used in technical contexts; often abbreviated as 'ID' in informal speech or documentation.

It depended on stable identifiers, which are labels or numbers that point to the same organization or event across different records.

The Conversation· 13 Aug 2026

Zuckoff uses these identifiers to help users detect specific smart-glasses models while ignoring Bluetooth signals from less creepy devices.

Ars Technica· 21 Aug 2026

From identify + -er.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Level B2 · Upper Intermediate
Frequency Occasional
Updated