noun
A substance that stimulates sexual desire. Often used in medical, pharmacological, or colloquial contexts.
ある種のハーブは催淫剤として知られている。
Certain herbs are known as aphrodisiacs.
Compound of 催淫 (さいいん, 'arousing sexual desire') + 剤 (ざい, 'agent, drug'). The exact historical derivation is uncertain, but the kanji composition transparently reflects the meaning.