Bursting with life — only there’s a large catch (9)
I believe the answer is:
yellowfin
'catch' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'bursting with life only there's a large' is the wordplay.
I cannot quite understand how this works, but
'with' could be 'w' (abbreviation) and 'w' is found within the answer.
'there's' could be 'n' (I've seen this in other clues) and 'n' is located in the answer.
'large' could be 'l' (eg in clothes sizes) and 'l' is found in the answer.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Another definition for yellowfin that I've seen is " Tuna".)