[1] : The Collaborative International Dictionary of English v.0.48

catastrophic \cat`astroph"ic\, a.
   of a pertaining to a catastrophe. --b. powell.
   1913 webster

[2] : WordNet (r) 2.0

catastrophic
     adj : extremely harmful; bringing physical or financial ruin; "a
           catastrophic depression"; "catastrophic illness"; "a
           ruinous course of action" syn: ruinous
see also:
ruinous 

[3] : Moby Thesaurus II by Grady Ward, 1.0

48 moby thesaurus words for "catastrophic":
   baneful, black, calamitous, cataclysmal, cataclysmic, consuming,
   consumptive, deadly, demolishing, demolitionary, depredatory,
   desolating, destroying, destructive, devastating, dire, disastrous,
   doomful, fatal, fateful, fratricidal, grievous, insurrectionary,
   internecine, nihilist, nihilistic, radical, ravaging, revolutional,
   revolutionary, revulsionary, revulsive, ruining, ruinous,
   self-destructive, subversionary, subversive, suicidal, sweeping,
   tragic, transilient, vandalic, vandalish, vandalistic, wasteful,
   wasting, withering, wreckful

Catastrophic >> C Words
Catastrophic, definition of term: Catastrophic
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