Blooming bed clothes don't wear out! (7)
I believe the answer is:
blasted
'blooming' is the definition.
(thesaurus)
'bed clothes don't wear out' is the wordplay.
'clothes' means one lot of letters goes inside another.
'don't wear out' becomes 'last' (something which lasts doesn't wear out quickly).
'bed' going around 'last' is 'BLASTED'.
(Other definitions for blasted that I've seen before include "Like the heath in Macbeth" , "darned" , "Flipping" , "Blown up" , "Damned" .)