annul annul /əˈnʌl/

verb

1. Cancel officially  ( annul , countermand , overturn , lift , repeal , rescind , reverse , revoke , vacate )
   cancel officially
    He revoked the ban on smoking
   He revoked the ban on smoking
    Lift an embargo
   lift an embargo
    Vacate a death sentence
   vacate a death sentence
   
2. Declare invalid  ( annul , avoid , nullify , invalidate , quash , void )
   declare invalid
    The contract was annulled
   The contract was annulled
    Void a plea
   void a plea