Silly dispute never ending, unfortunately (6)
I believe the answer is:
stupid
'silly' is the definition.
(thesaurus)
'dispute never ending unfortunately' is the wordplay.
'never ending' means to remove the last letter.
'unfortunately' is an anagram indicator.
'dispute' with its last letter taken off is 'disput'.
'disput' with letters rearranged gives 'STUPID'.
(Other definitions for stupid that I've seen before include "Ignorant" , "Senseless" , "Irresponsible" , "Not intelligent, thick" , "Idiot" .)