root 1. (operating system) The Unix superuser account (with user name "root" and user ID 0) that overrides file permissions. The term avatar is also used. By extension, the privileged system-maintenance login on any operating system.
See root mode, go root, wheel. [Jargon File] Last updated: 1994-10-27
2. (operating system) root directory. Last updated: 1996-11-21
3. (data) root node. Last updated: 1998-11-14