- hermetic ► ADJECTIVE 1) (of a seal or closure) complete and airtight. 2) insulated or protected from outside influences. 3) esoteric or cryptic: hermetic poems.DERIVATIVES hermetically adverb hermeticism noun.ORIGIN from Latin Hermes Trismegistus 'thrice-greatest Hermes' , the legendary founder of alchemy and astrology identified with the Greek god Hermes.
English terms dictionary. 2015.