1. Not up to expectations
   "a disappointing performance from one who had seemed so promising";
   - dissatisfactory, unsatisfying

1. Fail to meet the hopes or expectations of
   "greatly concerned not to disappoint a small child";
   - let down

See also: unsatisfactory

Type of: baffle, bilk [informal], cross, foil, frustrate, queer [informal], scotch, scupper [informal], spoil, thwart

Encyclopedia: Disappointing