House that Cocteau had to repair finally (5)
I believe the answer is:
tudor
'house' is the definition.
(royal house)
'that cocteau had to repair finally' is the wordplay.
'finally' says to take the final letters.
The final letters of 'that cocteau had to repair' are 'TUDOR'.
(Other definitions for tudor that I've seen before include "Welsh royal family" , "English royal dynasty" , "Style of architecture in 15th c. England" , "Mary" , "Former English royal house" .)