Endless disgrace is not real (4)
I believe the answer is:
sham
'not real' is the definition.
(I've seen this in another clue)
'endless disgrace' is the wordplay.
'endless' means to remove the last letter.
'disgrace' becomes 'shame' (synonyms).
'shame' with its last letter taken off is 'SHAM'.
'is' acts as a link.
(Other definitions for sham that I've seen before include "imitation" , "charade" , "Counterfeit or insincere" , "Mash, being counterfeit" , "Feign" .)