cray /kray/ n.
1. (properly, capitalized) One of the line of supercomputers designed by Cray Research. 2. Any supercomputer at all. 3. The canonical number-crunching machine.
The term is actually the lowercased last name of Seymour Cray, a noted computer architect and co-founder of the company. Numerous vivid legends surround him, some true and some admittedly invented by Cray Research brass to shape their corporate culture and image.