WordWeb Online

1. Not firm or firmly fixed; likely to fail or give way
   "the hinge is insecure"
    
2. Lacking in security or safety
   "an insecure future"; "his fortune was increasingly insecure";
   - unsafe
    
3. Lacking self-confidence or assurance
   "an insecure person lacking mental stability"
    
4. Not safe from attack
   - unsafe

See also: dangerous, out on a limb, overanxious, precarious, shaky, unassured, unfixed, unguaranteed, unprotected, unsafe, unsecured, vulnerable

Antonym: secure, untroubled

Encyclopedia: Insecure