Philtre, the name given to certain concoctions of herbs, often deleterious and poisonous, supposed to secure for the person administering it the love of the person to whom it was administered; these love potions were popular in the declining days of Greece and Rome, throughout mediæval Europe, and continue to be compounded to this day in the superstitious East.
Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)
Philpotts, Henry * Phiz