State of insensibility (6)
I believe the answer is:
stupor
'state of insensibility' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for stupor that I've seen before include "Proust found in dazed condition" , "State of near insensibility" , "State of being dazed or numb" , "State of insensibility or near-unconsciousness" , "Dazed condition as from drink or drugs" .)