username
nounUK /ˈjuːzəneɪm/
US /ˈjuːzərneɪm/
A username is a special name you use to log in to a computer or website.
I forgot my username, so I couldn't sign in to the game.
OTHER MEANINGS
2. The name that identifies a person on a computer network or online service.
Her username appeared next to every message she posted.
3. A name chosen by a user to represent themselves in an online community.
He picked a funny username for the forum.
4. The part of an email address before the @ symbol.
In sam@example.com, the username is sam.
5. A name used to identify a user in a multi-user computer system.
Each student was given a username to access the school computers.