Lingerie should not be worn out (9)
I believe the answer is:
underwear
'lingerie' is the definition.
(I know that underwear is a type of lingerie)
'should not be worn out' is the wordplay.
I cannot really see how this works, but
'not' could be 'un' (prefix meaning 'not') and 'un' is located in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for underwear that I've seen before include "Bloomers" , "Slip maybe" , "Clothing nearest the skin" , "Smalls,shorts,lingerie etc" , "Possibly slips" .)