1(of a seal or closure) complete and airtight:a hermetic seal that ensures perfect waterproofing
insulated or protected from outside influences:a hermetic society
2 (also Hermetic) relating to an ancient occult tradition encompassing alchemy, astrology, and theosophy:some saw in the Hermetic texts an anticipation of Christianity
difficult to understand because intended for a small number of people with specialized knowledge:obscure and hermetic poems