antaphrodisiac adj.

word-forming element of Greek origin meaning "against, opposed to, opposite of, instead," shortened to ant- before vowels and -h-, from Old French anti- and directly from Latin anti-, from Greek anti (prep.) "over, against, opposite; instead, in the place of; as good as; at the price of; for the sake of; compared with; in opposition to; in return; counter-," from PIE *anti "against," also "in front of, before" (from root *ant- "front, forehead," with derivatives meaning "in front of, before"), which became anti- in Italian (hence antipasto) and French.

It is cognate with Sanskrit anti "over, against," and Old English and- (the first element in answer). A common compounding element in Greek, in some combinations it became anth- for euphonic reasons. It appears in some words in Middle English but was not commonly used in English word formations until modern times. In a few English words (anticipate, antique) it represents Latin ante.

In noun compounds where it has the sense of "opposed to, opposite" (Antichrist, anti-communist) the accent remains on the anti-; in adjectives where it retains its old prepositional sense "against, opposed to," the accent remains on the other element (anti-Christian, anti-slavery).

"preparation or drug which excites sexual desire," 1719, from Latinized form of Greek aphrodisiakos "inducing sexual desire," from Aphrodisios, "sacred to Aphrodite, pertaining to Aphrodite," Greek goddess of love and beauty (see Aphrodite), whose name also meant "sexual pleasure; a temple of Aphrodite." As an adjective from 1775 (earlier was aphrodisical, 1719). Aphrodisian "devoted to sexual love" is attested from 1864.