Some feel big election setback is understandable (7)
I believe the answer is:
legible
'understandable' is the definition.
Both the definition and answer are adjectives. Perhaps you can see a link between them that I don't see?
'some feel big election setback' is the wordplay.
'some' indicates a hidden word (some parts of the word are used).
'setback' says the letters should be written in reverse.
'elbigel' is hidden in the letters of 'feel big election'.
'elbigel' reversed gives 'LEGIBLE'.
'is' is the link.
Can you help me to learn more?
(Other definitions for legible that I've seen before include "Decipherable" , "Possible to read" , "Clear enough to read" , "Readable" , "Capable to be read" .)