Carmen's pet distressed Cliff (10)
I believe the answer is:
escarpment
'cliff' is the definition.
(thesaurus)
'carmen's pet distressed' is the wordplay.
'distressed' indicates anagramming the letters.
'carmens'+'pet'='carmenspet'
'carmenspet' is an anagram of 'ESCARPMENT'.
(Other definitions for escarpment that I've seen before include "Bluff" , "Face" , "Precipitous side of hill" , "Long edge of plateau" , "Steep slope - map's centre (anag)" .)