B.O.

from WordNet (r) 3.0 (2006)

B.O.
    n 1: malodorousness resulting from a failure to bathe [syn:
         {body odor}, {body odour}, {B.O.}]

from The Collaborative International Dictionary of English v.0.48

Bo \Bo\, interj. [Cf. W. bw, an interj. of threatening or
   frightening; n., terror, fear, dread.]
   An exclamation used to startle or frighten. [Spelt also {boh}
   and {boo}.]
   [1913 Webster]

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

BO
       Back Orifice (CDC)

from Moby Thesaurus II by Grady Ward, 1.0

39 Moby Thesaurus words for "BO":
      bad breath, bad smell, beaded brow, beads of sweat, body odor,
      cold sweat, diaphoresis, exudate, exudation, fetidity, fetidness,
      fetor, foul breath, foul odor, frowst, graveolence, halitosis,
      honest sweat, lather, malodor, mephitis, miasma, nidor,
      noxious stench, offensive odor, perspiration, perspiration odor,
      reek, reeking, rotten smell, stench, stench of decay, stink,
      streams of sweat, sudor, sudoresis, sweat, swelter, water