WordWeb Online

1. Characterized by unrest or disorder
   "unquiet days of riots"; "following the assassination of Martin Luter King ours was an unquiet nation"; "spent an unquiet night tossing and turning"
    
2. Causing or fraught with or showing anxiety
   "an unquiet mind";
   - anxious, nervous, queasy, uneasy

See also: agitated, antsy [N. Amer, informal], disruptive, fidgety, fretful, itchy, keyed-up, on edge, restless, riotous, squalling, squally, troubled, tumultuous, turbulent, twitchy [informal], uneasy, wild

Antonym: quiet