Thrill so to see fluttery butterfly? (13)
I believe the answer is:
tortoiseshell
'butterfly?' is the definition.
(tortoiseshell butterfly is a kind of butterfly)
'thrill so to see fluttery' is the wordplay.
'thrill so to see' can be anagrammed to 'TORTOISESHELL'.
Though, I am not sure how this is indicated.
Can you help me to learn more?
(Other definitions for tortoiseshell that I've seen before include "Butterfly - cat" , "Mottled plated ornamental substance" , "Domestic cat mottled in brownish-yellow and black" , "Ornamental material" , "Domestic cat - or little shoes (anag)" .)