Untrue (5)

'untrue' is the definition.
(I know that untrue can be written as false)
This is all the clue.
(Other definitions for false that I've seen before include "Not genuine or real" , "Not in accordance with fact" , "Incorrect" , "Untrue - treacherous - counterfeit" , "Spurious, untrue" .)
'untrue' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for not so that I've seen before include "Wrong" , "Less" , "untrue" .)