Hi Peadar
First three letters are common synonym for playground reversed ('in retrospect'), the rest is an anagram of 'superb' minus 'p' ( quiet), so the definition is 'demonic dog'.
Rigatoni I knew the dog but to my shame I'd never heard of the author, but got the answer from the wordplay which I agree was very satisfying, then checked with Google & wondered how I had been so ignorant!