Musical instrument of Shakespearean character (5)
I believe the answer is:
viola
I believe this clue is a double definition.
'musical instrument' is the first definition.
(viola is a kind of musical instrument)
'shakespearean character' is the second definition.
(I've seen this before)
'of' acts as a link.
(Other definitions for viola that I've seen before include "Sebastian's twin (Twelfth Night)" , "Musical instrument "Twelfth Night" character" , "Sebastian's sister" , "Large fiddle" , "Page" .)