medicament

C. G. Jungの "Modern Man in Search of a Soul" を読んでいます。
今日取り上げる単語も第5章 'The Stages of Life' からの引用です。

Before the nineteenth century the thyroid was regarded as a meaningless organ, merely because it was not understood. It would be equally short-sighted of us today to call the primordial images senseless. For me these images are something like psychic organs, and I treat them with the very greatest care. It happens sometimes that I must say to an older patient: "Your picture of God or your idea of immortality is atrophied; consequently your psychic metabolism is out of gear." The ancient athanasias pharmakon, the medicament of immortality, is more profound and meaningful than we supposed.

medicament of immortalityは不老不死の薬もしくは治療と推測できますが、"medicine" の親戚のような "medicament" の意味を辞書で確認します。

・Oxford English Dictionary: A substance used for medical treatment.: Yet some rather toxic metals, albeit in insoluble form, have been used as medicaments: Bismuth, for example, as an antacid.
・Collins Dictionary: a medicine or remedy in a specified formulation: He registered 321 licences for the application of human peptides as medicaments for rare diseases.
・Merriam-Webster's Online Dictionary: a substance used in therapy: in the 19th century a physician's bag of medicaments most likely included powerful opiates

"medicine" と同義語ですね。
A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease.（Wikipediaからの抜粋）