System V System 5 Unix System V 1. The other major versions of the {Unix} {operating system} apart from {BSD}. Developed by {AT&T}. Later versions of Unix such as {SunOS} combined the best features of {System V} and {BSD} Unix. (1994-10-31) [Differences?] 2. A supplier of {Unix} {open systems} for {Intel x86} processors. They supply products from {SCO} and {Solaris} and offer general support for {Unix}, {TCP/IP}, and {Internet}. They serve and create third-party {WWW} pages and provide on-line support for commercial and non-commercial applications. (http://systemv.com/). See also {System V Interface Definition}. (1994-12-12)