Fish guzzler's sorrow after missing starter (5)
I believe the answer is:
egret
'fish guzzler's' is the definition.
The answer and definition can be both animals as well as being singular nouns.
Maybe there's a link between them I don't understand?
'sorrow after missing starter' is the wordplay.
'sorrow' becomes 'regret' (regret is a kind of sorrow).
'after missing starter' means to remove the first letter.
'regret' with its initial letter removed is 'EGRET'.
Can you help me to learn more?
(Other definitions for egret that I've seen before include "Greet (anag) -- wading bird" , "(Usually) white heron" , "Stork-like bird" , "White wading bird" , "One wading" .)