anaphrodisiac

adj

1. Antaphrodisiac (capable of reducing the sex drive).

   “Tobacco and the plant valerian are also considered to be anaphrodisiac in their effects, diminishing sexual inclination.”

noun

1. An antaphrodisiac (substance which reduces the sex drive).

   “Among this group are the solanacei alkaloids, that have a decided anti-sexual tendency. Such plants and similar anaphrodisiacs were often used, especially in the Middle Ages, to promote asceticism and, in the case of monks, to diminish fleshly desires.”