The evil genïus of a house: a Nemesis. Cicero says: “Who meditated killing himself that he might become the Alastor of Augustus, whom he hated.” Shelley has a poem entitled “Alastor, or The Spirit of Solitude”. The word is Greek (alastor, the avenging god, a title applied to Zeus); the Romans had their Jupiter Vindex; and we read in the Bible, “Vengeance is mine. I will repay, saith the Lord” (Romans xii. 19).
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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