It's a catastrophe! (7)
I believe the answer is:
debacle
'it's a catastrophe' is the definition.
(a debacle is a catastrophe or disaster)
This is all the clue.
(Other definitions for debacle that I've seen before include "A sound defeat" , "Rout; disaster" , "Fiasco, a right mess" , "Sudden and ignominious failure" , "Humiliating failure" .)