Stick with fish after chowder starter (5)
I believe the answer is:
cling
'stick' is the definition.
(I know that stick can be written as cling)
'fish after chowder starter' is the wordplay.
'fish' becomes 'ling' (ling is a kind of fish).
'after' is a charade indicator (letters next to each other).
'starter' suggests taking the first letters.
The initial letter of 'chowder' is 'c'.
'ling' put after 'c' is 'CLING'.
'with' acts as a link.
(Other definitions for cling that I've seen before include "Stick close (to surface)" , "Keep hold" , "Stick - tinkle" , "Hold on tightly, refuse to abandon" , "have emotional attachment?" .)