Begun realignment to reveal fake (6)
I believe the answer is:
unreal
'fake' is the definition.
('unreal' can be similar in meaning to 'fake')
'begun realignment to reveal' is the wordplay.
'to reveal' indicates the answer is hidden within the clue.
'UNREAL' is hidden in the letters of 'begun realignment'.
(Other definitions for unreal that I've seen before include "Fanciful" , "Lacking in substance" , "Not true to life" , "Existing only in the imagination, not actual" , "Lacking material form" .)