Damage pants out in rain (9)
I believe the answer is:
ruination
'damage' is the definition.
(thesaurus)
'pants out in rain' is the wordplay.
'pants' is an anagram indicator (UK informal term for 'nonsense' or 'rubbish').
'out'+'in'+'rain'='outinrain'
'outinrain' is an anagram of 'RUINATION'.
(Other definitions for ruination that I've seen before include "End" , "In financial disaster" , "A fruit; Chuck ---, rock 'n' roll singer" , "Utter destruction" , "total disaster" .)