The Collaborative International Dictionary of English v.0.48:

Calamitous \Ca*lam"i*tous\, a. [L. Calamitosus; cf. F.
   calamiteux.]
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   1. Suffering calamity; wretched; miserable. [Obs.]
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            Ten thousands of calamitous persons.  --South.
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   2. Producing, or attended with distress and misery; making
      wretched; wretched; unhappy. "This sad and calamitous
      condition." --South. "A calamitous prison" --Milton.

   Syn: Miserable; deplorable; distressful; afflictive;
        wretched; grievous; baleful; disastrous; adverse;
        unhappy; severe; sad; unfortunate. --
        Ca*lam"i*tous*ly, adv. -- Ca*lam"i*tous*ness, n.
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