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

UNTRUE is a 6 letter word that starts with U.

1. \Un*true"\, a.
   1. Not true; false; contrary to the fact; as, the story is
      untrue.
   
   2. Not faithful; inconstant; false; disloyal. --Chaucer.
   
   

2. \Un*true\, adv.
   Untruly. [Obs. or Poetic] --Chaucer.