Fleas flying? Not true (5)

I believe the answer is:

false

'not true' is the definition.
(I know this)

'fleas flying?' is the wordplay.
'flying?' indicates an anagram (letters fly around into new positions).
'fleas' is an anagram of 'FALSE'.

(Other definitions for false that I've seen before include "Erroneous" , "Not true" , "Spurious, untrue" , "Untrue - treacherous - counterfeit" , "Not genuine or real" .)

I've seen this clue in The Daily Express.

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