WordWeb Online

1. Difficult to solve or alleviate
   "uncontrollable pain"
   - unmanageable
    
2. Failing to follow rules or orders
   "the little boy's parents think he is spirited, but his teacher finds him uncontrollable"
   - indocile, ungovernable, unruly
    
3. Incapable of being controlled or managed
   "uncontrollable children"
   - uncorrectable, unmanageable
    
4. Impossible to repress or control
   "uncontrollable laughter"
   - irrepressible

See also: difficult, incorrigible, intractable, uncontrolled, unmanageable