n (computing) A computer operating system that shares the original source code by Dennis Ritchie and Ken Thompson, currently owned by Novell.
n (computing) An operating system largely compatible with Unix that qualifies for use of the UNIX trademark, currently owned by The Open Group.
n (computing, informal) The above plus Unix-like operating systems similar to Unix but not qualifying for use of the UNIX trademark.
n (computing) The group of Unix operating systems as a whole.
n Unix, the original operating system developed by K&R at Bell Labs
n Unix, the operating system standard shepherded by The OPEN Group
n (software) Any Unix-like operating system, including Unix.
n (software) Collectively, Unix and unix-like operating systems.