It'a an adjective describing someone who loves a certain playwright. Not a word I knew, but the construction is fair:
Sut up + adjective for a canary, say. That gives an improbable word ( for me) but I looked it up and learnt something new!
Thank you sudokulover. I did have the right wordplay but stupidly took the first letter instead of the last for one of the words. Your post let me look at the clue again and iron out my brain blip. So now all's done, no excuse not to go and do someting more useful (sigh)