Dictionary.com
Thesaurus.com

username

American  
[yoo-zer-neym] / ˈyu zərˌneɪm /

noun

Computers.
  1. Also called sign-in name,.  Also called login name,.  Also called sign-on name.  Also called logon name,.  a unique sequence of characters used to identify a user and allow access to a computer system, computer network, or online account.

  2. the part of an email address before the @ sign.


username British  
/ ˈjuːzəˌneɪm /

noun

  1. computing a name that someone uses for identification purposes when logging onto a computer, using chatrooms, or as part of his or her e-mail address

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of username

First recorded in 1970–75; user 1 ( def. ) + name ( def. )

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Ilyas Lebleu, an A.I. research student based in France who edits Wikipedia under the username Chaotic Enby, first wrote the proposal that was debated and adopted as the site’s A.I. ban.

From Slate • Apr. 1, 2026

The agent determined that the host computer had software with the username “astro99999” and an IP address linked to McClain’s home address in Menifee.

From Los Angeles Times • Mar. 19, 2026

She can be reached on Signal at the username JournoLiz.80.

From The Wall Street Journal • Mar. 5, 2026

“It’s rare we get a non-temp market with so much attention and liquidity like this,” says a 31-year-old New York-based Kalshi trader whose username is NelsonOrAri.

From Barron's • Jan. 26, 2026

“What do you want your username to be?” she asks me.

From "The Wrong Way Home" by Kate O’Shaughnessy