A term used in Religious circles, of ancient times, to refer to a male's semen. Other terms were Water of Wisdom, Seed of Life.
In some cultures, it was required that younger males fellate their elders, in order to partake in the waters of wisdom, that was believed to be contained with the semen from Older Males.
Other religious beliefs (such as Christianity), contented that the waste of one's semen without the express purpose of procreating life, was a sin, which include masturbation.
Pre Industrial societies also believed that semen, like blood, held magical powers, and was to be revered.