Toad, rabbit and sea dog (10)
I believe the answer is:
natterjack
'toad' is the definition.
(natterjack is a kind of toad)
'rabbit and sea dog' is the wordplay.
'rabbit' becomes 'natter' (both can mean to talk excessively).
'and' says to put letters next to each other.
'sea dog' becomes 'jack' (both can mean a sailor).
'natter'+'jack'='NATTERJACK'
(Another definition for natterjack that I've seen is " Small toad".)
I've seen this clue in The Guardian.
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