dimple in the middle of the upper lip, 1703, medical Latin, from Latinized form of Greek philtron, literally "love charm" (see philtre).
Entries linking to philtrum
philtre n.
also philter, "love potion, potion supposed to have the power of exciting sexual love," 1580s, from French philtre (1560s), from Latin philtrum (plural philtra) "love potion," from Greek philtron "a love-charm," properly philētron, literally "to make oneself beloved," from philein "to love" (from philos "loving;" see philo-) + instrumental suffix -tron.