CALAMITY, n. A more than commonly plain and unmistakable reminder that the affairs of this life are not of our own ordering. Calamities are of two kinds: misfortune to ourselves, and good fortune to others.

Ambrose Bierce (1842-1914?) American writer and journalist

“Calamity,” The Cynic’s Word Book (1906)
    (Source)

Included in The Devil's Dictionary (1911).