<communications, networking> (STB) Any electronic device designed to produce output on a conventional televesion set (on top of which it nominally sits) and connected to some other communications channels such as telephone, ISDN, optical fibre or cable. The STB usually runs software to allow the user to interact with the programmes shown on the television in some way.
Online Media are one STB manufacturer.
Try this search on Wikipedia, OneLook, Google
Nearby terms: Set Priority Level « SETS « set theory « set-top box » SEUS » seven layer model » Seven-Segment Display