[1] : The Collaborative International Dictionary of English v.0.48

betray \betray"\ b-etr=a", v. t. imp.  p. p.
   betrayed -tr=ad"; p. pr.  vb. n. betraying. oe.
   betraien, bitraien; pref. be- + of. tra"ir to betray, f.
   trahir, fr. l. tradere. see traitor.
   1. to deliver into the hands of an enemy by treachery or
      fraud, in violation of trust; to give up treacherously or
      faithlessly; as, an officer betrayed the city.
      1913 webster

            jesus said unto them, the son of man shall be
            betrayed into the hands of men.       --matt. xvii.
                                                  22.
      1913 webster

   2. to prove faithless or treacherous to, as to a trust or one
      who trusts; to be false to; to deceive; as, to betray a
      person or a cause.
      1913 webster

            but when i rise, i shall find my legs betraying me.
                                                  --johnson.
      1913 webster

   3. to violate the confidence of, by disclosing a secret, or
      that which one is bound in honor not to make known.
      1913 webster

            willing to serve or betray any government for hire.
                                                  --macaulay.
      1913 webster

   4. to disclose or discover, as something which prudence would
      conceal; to reveal unintentionally.
      1913 webster

            be swift to hear, but cautious of your tongue, lest
            you betray your ignorance.            --t. watts.
      1913 webster

   5. to mislead; to expose to inconvenience not foreseen to
      lead into error or sin.
      1913 webster

            genius . . . often betrays itself into great errors.
                                                  --t. watts.
      1913 webster

   6. to lead astray, as a maiden; to seduce as under promise
      of marriage and then abandon.
      1913 webster

   7. to show or to indicate; -- said of what is not obvious at
      first, or would otherwise be concealed.
      1913 webster

            all the names in the country betray great antiquity.
                                                  --bryant.
      1913 webster
see also:
betrayed betraying traitor 

[2] : WordNet (r) 2.0

betraying
     adj : revealing unintentionally; "a betraying blush spread over
           her face"

Betraying >> B Words
Betraying, definition of term: Betraying
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