Gone numb (4)
I believe the answer is:
dead
I believe this is a double definition.
'gone' is the first definition.
(gone can mean deceased)
'numb' is the second definition.
(eg a dead arm)
(Other definitions for dead that I've seen before include "Devoid of life" , "Six feet under" , "dull" , "As was Monty Python's parrot" , "No longer relevant" .)