No end of a dude, he’s useless! (3)
I believe the answer is:
dud
I believe this clue is a quadruple definition!!
'no' is the first definition.
(thesaurus)
'end of a dude' is the second definition.
The answer and definition can be both people as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'he's' is the third definition.
'useless' is the fourth definition.
(I've seen this before)
Can you help me to learn more?
(Other definitions for dud that I've seen before include "'Flop, turkey (3)'" , "A palindromic failure" , "Ineffectual person" , "Palindrome for a flop" , "Valueless" .)