her·​met·​ic (ˌ)hər-ˈme-tik How to pronounce hermetic (audio)
variants or less commonly hermetical
often capitalized
: of or relating to the mystical and alchemical writings or teachings arising in the first three centuries a.d. and attributed to Hermes Trismegistus
: relating to or characterized by subjects that are mysterious and difficult to understand : relating to or characterized by occultism or abstruseness : recondite
a hermetic discussion
[from the belief that Hermes Trismegistus invented a magic seal to keep vessels airtight]
: airtight
hermetic seal
: impervious to external influence
trapped inside the hermetic military machineJack Newfield
: recluse, solitary
leads a hermetic life

Did you know?

Hermetic Has Origins in Greek Mythology

Hermetic derives from Greek via the Medieval Latin word hermeticus. When it first entered English in the early 17th century, hermetic was associated with writings attributed to Thoth, the Egyptian god of wisdom. Thoth, whom the Greeks called Hermes Trismegistus ("thrice-great Hermes"), was believed to be the author of a number of mystical, philosophical, and alchemistic works. The obscure subject matter of these works may have made them difficult to wade through, for soon English speakers were also applying hermetic to things that were beyond ordinary human comprehension. Additionally, Hermes Trismegistus was said to have invented a magic seal that could keep vessels airtight. Hermetic thus came to mean "airtight," both literally and figuratively. These days, it can also sometimes mean "solitary."

Example Sentences

wrote hermetic poetry whose sole intended readership was himself
Recent Examples on the Web The question that will soon confront American voters and the press is whether campaigning of this nature will have legs beyond the hermetic boundaries of Florida. Michael Hiltzik, Los Angeles Times, 17 May 2023 But while the latter pairs and their imitators grew to ruin only all sports radio markets, the hermetic reality-distortion that defined the outraged Cuban-American talk radio community has been applied to the country as a whole by conservative media, eventually absorbing the White House. Jeb Lund, The New Republic, 26 Oct. 2020 Hierophany & Hedge is a shop that sells cauldrons, crystals, candles, incense, eclipse reliquaries and other hermetic devices, magic books, Pharaonic tomb and other exotic reagents, talismans, wands and more. Charles Infosino, The Enquirer, 10 May 2023 This offers a unique opportunity to access this incredible world of new possibilities, proving that this traditional, often conservative and hermetic world of high-end, rare, extra old, dark spirits, can successfully merge with new technology with great success. Joseph V Micallef, Forbes, 21 Apr. 2022 Rural Suffolk County, in Mr. Blythe’s depiction, was a hermetic, semi-feudal society, a place out of time where life was shaped by the cycle of the seasons and modernity had little purchase. Clay Risen, New York Times, 8 Feb. 2023 The actress had been nominated for Outstanding Lead Actress in a Limited Series or Movie for her role in the breakout Netflix series Unorthodox as Esther Shapiro, a young 19-year-old bride from a hermetic, heavy-on-tradition, Yiddish-speaking, ultra-Orthodox community in Williamsburg, Brooklyn. Liana Satenstein, Vogue, 21 Sep. 2020 At the same time here in rural Japan—feudal, hermetic, entirely unique—an era of peace and prosperity was underway in a society as intricate as a mechanical clock, and this remote mountain hostelry was welcoming a daily parade of traveling samurai, scholars, poets and sightseers. Hiroshi Okamoto, Smithsonian Magazine, 9 July 2020 Set in a dark, cluttered space — the tract house where hermetic Charlie’s soul unfolds — The Whale feels as contrived as a stage play. Armond White, National Review, 15 Mar. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'hermetic.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


Medieval Latin hermeticus, from Hermet-, Hermes Trismegistus

First Known Use

1605, in the meaning defined at sense 1a

Time Traveler
The first known use of hermetic was in 1605


Dictionary Entries Near hermetic

Cite this Entry

“Hermetic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hermetic. Accessed 5 Jun. 2023.

Kids Definition


her·​met·​ic (ˌ)hər-ˈmet-ik How to pronounce hermetic (audio)
hermetically adverb

Medical Definition


her·​met·​ic (ˌ)hər-ˈmet-ik How to pronounce hermetic (audio)
: being airtight or impervious to air
hermetically adverb

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