Her-mēt'ic or Her-mēt'ic-al, a.
a. [Fr. hermétique, Sp. hermetico, It. ermetico, from the Egyptian Hermes Trismegistus, or Hermes the thrice-greatest, the fabled inventor of alchemy.]
Sense 1. Pertaining to chemistry; chemical.
Just as the dream of the philosopher's stone induces dupes, under the more plausible delusions of the hermetic art, to neglect all rational means of improving their fortunes. Burke.
Sense 2. Pertaining or belonging to that species of philosophy which pretends to solve and explain all the phenomena of nature from the three chemical principles, salt, sulphur, and mercury; as, the hermetic philosophy.
Sense 3. Pertaining, or belonging, to the system which explains the causes of diseases and the operations of medicine, on the principles of the hermetical philosophy, and particularly on the system of an alkali and acid; as, hermetical physic or medicine.
Sense 4. Perfectly close, so that no air, gas, or spirit can escape; as, an hermetic seal. The hermetic seal is formed, in glass vessels, by heating the neck of a vessel till it is soft, and then twisting it till the aperture, or passage, is accurately closed.
Hermetic books. (a.) Books of the Egyptians, which treat of astrology. Bryant. (b.) Books which treat of universal principles, of the nature and orders of celestial beings, of medicine, and other topics. Enfield.