Whats is Hermetic???

hermetic

həːˈmɛtɪk/

adjective

1. 1.

   (of a seal or closure) complete and airtight.

   "a hermetic seal that ensures perfect waterproofing"

   synonyms:

   airtight, tight, sealed, shut; More
2. 2.

   relating to an ancient occult tradition encompassing alchemy, astrology, and theosophy.

   "some saw in the Hermetic texts an anticipation of Christianity"

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