Joint doctor violated (8)
I believe the answer is:
dovetail
'joint' is the definition.
(I've seen this before)
'doctor violated' is the wordplay.
'doctor' indicates an anagram.
'violated' anagrammed gives 'DOVETAIL'.
(Other definitions for dovetail that I've seen before include "Fit snugly" , "Joint with fan-shaped tenon" , "Fit closely together like white bird and appendage" , "Joint of tenon and mortise" , "Joint - fit neatly" .)