An accident or chance event, especially one that happens by luck or coincidence.
From Latin 'fortuitus' (accidental, by chance), derived from 'fors' (chance, fortune). The word entered Middle English through Old French and retains its meaning of pure accidental occurrence.
Before insurance and risk management, 'fortuity' was simply what you called bad luck—a ship sinking, a house fire, a crop failure. Now it's a technical legal term separating 'acts of God' (fortuities) from negligence, showing how medieval concepts became modern bureaucracy!
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