River of Shakespeare's Stratford (4)
I believe the answer is:
avon
'river of shakespeare's stratford' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for avon that I've seen before include "River flowing through Bristol to the Severn" , "Bristol's river" , "English river, flows through Stratford" , "English river name in multiple use" , "Bath's river" .)