E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
A draught or charm to incite in another the passion of love. The Thessalian philters were the most renowned, but both the Greeks and Romans used these dangerous potions, which sometimes produced insanity. Lucretius is said to have been driven mad by a love-potion, and Caligulas death is attributed to some philters
administered to him by his wife, Cæsonia. Brabantio says to Othello
Thou hast practised on her [Desdemona] with foul charms,