Cast, getting fine fish (5)
I believe the answer is:
fling
'cast' is the definition.
(thesaurus)
'fine fish' is the wordplay.
'fine' becomes 'f' (abbreviation).
'fish' becomes 'ling' (ling is a kind of fish**).
'f'+'ling'='FLING'
'getting' is the link.
(Other definitions for fling that I've seen before include "good time" , "Hurl" , "quick one?" , "Throw - short affair" , "Brief affair; throw" .)