Joke at the end unsavoury and feeble (4)
I believe the answer is:
puny
'feeble' is the definition.
(I've seen this before)
'joke at the end unsavoury' is the wordplay.
'joke' becomes 'pun' (punning is a kind of joking).
'at the end' says to take the final letters.
The last letter of 'unsavoury' is 'y'.
'pun'+'y'='PUNY'
'and' acts as a link.
(Other definitions for puny that I've seen before include "Small and feeble" , "Weak - unimportant" , "in need of development" , "Frail and weedy" , "Slight" .)