The Collaborative International Dictionary of English v.0.48:

Bos \Bos\, prop. n. [L., ox, cow.] (Zool.)
   A genus of ruminant quadrupeds, including the wild and
   domestic cattle, distinguished by a stout body, hollow horns,
   and a large fold of skin hanging from the neck.
   [1913 Webster]

V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006):

BOS
       Basic Operating System (AIX, IBM)


V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006):

BOS
       Batch Operating System (OS, Honeywell)


V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006):

BOS
       Basic Overseer Server (AFS)