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

Derived forms: untruer, untruest

See also: false, inconstant, uneven, unfaithful

Encyclopedia: Untrue