WordWeb Online

1. Not according with the facts
   "unfortunately the statement was simply untrue"
    
2. Not true to an obligation or trust
   "is untrue to his highest opportunity and duty"
    
3. Not accurately fitted; not level
   "off-level floors and untrue doors and windows";
   - out of true
    
4. (used especially of persons) not dependable in devotion or affection; unfaithful
   "when lovers prove untrue";
   - false

Derived forms: untruest, untruer

See also: false, inconstant, uneven, unfaithful

Encyclopedia: Untrue