State of undress (6)
I believe the answer is:
nudity
'state of undress' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for nudity that I've seen before include "State of being without clothes" , "Untidy (anag) -- result of being in one's birthday suit" , "Going without garments" , "State of complete undress" , "state some sleepers prefer" .)