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

disappoint \dis`appoint"\, v. t. imp.  p. p. disapointed;
   p. pr.  vb. n. disappointing. of. desapointier, f.
   d'esappointer; pref. des- l. dis- + apointier, f.
   appointier, to appoint. see appoint.
   1. to defeat of expectation or hope; to hinder from the
      attainment of that which was expected, hoped, or desired;
      to balk; as, a man is disappointed of his hopes or
      expectations, or his hopes, desires, intentions,
      expectations, or plans are disappointed; a bad season
      disappoints the farmer of his crops; a defeat disappoints
      an enemy of his spoil.
      1913 webster

            i was disappointed, but very agreeably. --macaulay.
      1913 webster

   note: disappointed of a thing not obtained; disappointed in a
         thing obtained.
         1913 webster

   2. to frustrate; to fail; to hinder of result.
      1913 webster

            his retiring foe
            shrinks from the wound, and disappoints the blow.
                                                  --addison.

   syn: to tantalize; fail; frustrate; balk; baffle; delude;
        foil; defeat. see tantalize.
        1913 webster
see also:
disapointed disappointing appoint tantalize 

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

disappointing \disappointing\ a.
   defeating one's expectations or hopes; failing to fulfill
   one's expectations or hopes; as, a disappointing result; a
   disappointing crop yield.
   pjc

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

disappointing \disappointing\ n.
   the act of disappointing someone.

   syn: disappointment, dashing hopes.
        wordnet 1.5

[4] : WordNet (r) 2.0

disappointing
     adj : not up to expectations; "a disappointing performance from
           one who had seemed so promising" syn: dissatisfactory,
            unsatisfying
see also:
dissatisfactory unsatisfying 

[5] : Moby Thesaurus II by Grady Ward, 1.0

23 moby thesaurus words for "disappointing":
   disconcerting, discouraging, disheartening, displeasing,
   dissatisfactory, falling short, inadequate, incommensurate,
   inferior, insufficient, not good enough, pathetic, poor, sad,
   second best, second-rate, sorry, tantalizing, teasing,
   unfulfilling, ungratifying, unsatisfactory, unsatisfying

Disappointing >> D Words
Disappointing, definition of term: Disappointing
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