philtre n.

before vowels phil-, word-forming element meaning "loving, fond of, tending to," from Greek philos (adj.) "dear, loved, beloved," as a noun, "friend," from philein "to love, regard with affection," a word of unknown origin. Productive of a great many compounds in ancient Greek (such as philokybos "a lover of dice-play"). Opposed to miso-. Compare -phile.

dimple in the middle of the upper lip, 1703, medical Latin, from Latinized form of Greek philtron, literally "love charm" (see philtre).