Disaster (4)
'disaster' is the definition.
(synonyms)
This is all the clue.
(Other definitions for catastrophe that I've seen before include "Sudden disaster" , "Terrible event" , "final event" , "Destructive event" , "Event causing great suffering" .)
'disaster' is the definition.
(I know that disaster can be written as calamity)
This is the entire clue.
(Other definitions for calamity that I've seen before include "Musical set in Deadwood" , "Tragedy" , "Martha Jane Cannary" , "Disaster for wild west Jane" , "Catastrophe" .)
'disaster' is the definition.
(ruin can mean disaster or catastrophe)
This is the entire clue.
(Other definitions for ruin that I've seen before include "Scotch" , "financial disaster" , "Complete collapse or destruction" , "Utter destruction or downfall" , "building now demolished" .)
'disaster' is the definition.
(synonyms)
This is the entire clue.
(Other definitions for debacle that I've seen before include "Sudden disastrous collapse or defeat" , "Pasting" , "Rout; fiasco" , "great failure" , "foul-up" .)