Debt of nature

death.

See also: Debt

References in classic literature ?
Philippa has long paid the Debt of Nature, Her Husband however still continues to drive the Stage-Coach from Edinburgh to Sterling:-- Adeiu my Dearest Marianne.
That both your debts are paid in the one great debt of nature.
His wife and daughter saw the dismal pageant from a distance, and alarmed the neighborhood with their cries; they thought the poor man had suddenly settled the great debt of nature in one of his wayward moods.