operating system /U-S-G yoo' niks/ RefeRS to AT&T Unix commercial veRSions after VeRSion 7, especially System III and System V releases 1, 2, and 3. So called because during most of the lifespan of those veRSions AT&T' s support crew was called the "Unix Support Group". Compare BSD. [Jargon File] (1997-02-20)