hermetic
Americanadjective
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made airtight by fusion or sealing.
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not affected by outward influence or power; isolated.
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(sometimes initial capital letter) of, relating to, or characteristic of occult science, especially alchemy.
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(initial capital letter) of or relating to Hermes Trismegistus or the writings ascribed to him.
adjective
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of or relating to Hermes Trismegistus or the writings and teachings ascribed to him
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of or relating to ancient science, esp alchemy
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esoteric or recondite
adjective
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sealed so as to be airtight
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hidden or protected from the outside world
Other Word Forms
- hermetically adverb
- unhermetic adjective
Etymology
Origin of hermetic
1630–40; < Medieval Latin hermēticus of, pertaining to Hermes Trismegistus, equivalent to Latin Hermē ( s ) Hermes + -ticus -tic
Explanation
If you want to keep cookies crisp for a long time, store them in a jar with a hermetic, or airtight, seal. Hermetic means sealed so that no air can get in. The word can be used metaphorically as well. A child who is completely protected from the outside world might be said to come from a hermetic environment. The word comes from the name of the Greek god, Hermes Trismegistus, who was a magician and alchemist and was credited with creating the process for making a completely airtight glass tube, a god-like feat if there ever was one.
Vocabulary lists containing hermetic
100 SAT Words Beginning with "H"
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30 GRE Words Beginning with "G" and "H"
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"Maus II: And Here My Troubles Began" by Art Spiegelman
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
The country had enjoyed a decade-long democratic experiment after a history of hermetic military rule.
From Barron's • Dec. 21, 2025
MIT is an enclave even within the hermetic world of Cambridge academia—a place where complex, bleeding-edge ideas spawn from sterile labs and filthy dorm rooms.
From The Wall Street Journal • Nov. 22, 2025
Previous generations didn’t have the chance to taste some version of the hermetic bliss millions of us were exposed to over the past five years.
From Salon • Mar. 26, 2025
The femtosecond laser welds offer superior strength with hermetic sealing at a compelling cost.
From Science Daily • May 2, 2024
I felt the warm tug of the past and the melancholy of absence—all of it a little jarring, accustomed as I was to the hermetic and youthful world of college.
From "Becoming" by Michelle Obama
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
