Cameron's disastrous affair (7)
I believe the answer is:
romance
'affair' is the definition.
(I've seen this in another clue)
'cameron's disastrous' is the wordplay.
'disastrous' indicates anagramming the letters.
'cameron' is an anagram of 'ROMANCE'.
(Other definitions for romance that I've seen before include "Group of languages" , "Court" , "Novel (or often its main theme)" , "(Wonderful) piece of fiction" , "Make up stories - Menorca (anag)" .)