Having left a valid will (7)
I believe the answer is:
testate
'having left a valid will' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for testate that I've seen before include "Having written a valid will" , "Leaving a will" , "Having made a legal will" , "With a legally valid will" , "Having made a will before death" .)