Cloak one sleeps rough in? (7)
I believe the answer is:
pelisse
'cloak' is the definition.
(I know that pelisse is a type of cloak)
'one sleeps rough in?' is the wordplay.
'one' becomes 'i' (Roman numeral).
'rough' is an anagram indicator (a rough or broken ordering of the letters).
'in?' means one lot of letters goes inside another.
'sleeps' with letters rearranged gives 'pelsse'.
'i' going into 'pelsse' is 'PELISSE'.
(Other definitions for pelisse that I've seen before include "coat" , "In a military cloak" , "Long cloak" , "Sleeveless cape" , "one worn by lady" .)