SOS - technical definition

(1) (Silicon On Sapphire) An MOS chip-fabrication method that places a thin layer of silicon over a sapphire substrate (base). This technique was used for earlier LSI fabrication, but not considered useful for higher-density VLSI chips. See SOI.

(2) (Systems On Silicon) A complete system on a single chip. See SoC.

(3) (Server Operating System) An operating system that resides on the server.

(4) (Sophisticated Operating System) The operating system used on the Apple III. See Apple III.