The Collaborative International Dictionary of English v.0.48:

Bom \Bom\, n. (Zool.)
   A large American serpent, so called from the sound it makes.
   [1913 Webster]

V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

BOM
       Byte Order Mark (Unicode)


V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

BOM
       Beginning of Message