made airtight by fusion or sealing.
not affected by outward influence or power; isolated.
(sometimes initial capital letter) of, relating to, or characteristic of occult science, especially alchemy.
(initial capital letter) of or relating to Hermes Trismegistus or the writings ascribed to him.

Also her·met·i·cal.

Origin of hermetic

1630–40; < Medieval Latin hermēticus of, pertaining to Hermes Trismegistus, equivalent to Latin Hermē(s) Hermes + -ticus -tic
Related formsun·her·met·ic, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for hermetic

impervious, sealed, shut, tight, waterproof, watertight

Examples from the Web for hermetic

Contemporary Examples of hermetic

Historical Examples of hermetic

  • It amounted to a surgical replacement of one hermetic elite by another.

    After the Rain

    Sam Vaknin

  • Detailed exposition of the Hermetic writings will here be impossible.

  • Certainly it is not so used ordinarily in the Hermetic writings.

  • “The priests must be hiding the Hermetic wisdom on purpose,” said Lucius.

    The Tour

    Louis Couperus

  • At that time Paris was the centre of the hermetic science in France.


    J. K. Huysmans

British Dictionary definitions for hermetic




sealed so as to be airtight
hidden or protected from the outside world
Derived Formshermetically, adverb

Word Origin for hermetic

C17: from Medieval Latin hermēticus belonging to Hermes Trismegistus, traditionally the inventor of a magic seal



of or relating to Hermes Trismegistus or the writings and teachings ascribed to him
of or relating to ancient science, esp alchemy
esoteric or recondite

Word Origin for Hermetic

see hermetic
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for hermetic

c.1600 (implied in hermetically), "completely sealed," also (1630s) "dealing with occult science or alchemy," from Latin hermeticus, from Greek Hermes, god of science and art, among other things, identified by Neoplatonists, mystics, and alchemists with the Egyptian god Thoth as Hermes Trismegistos "Thrice-Great Hermes," who supposedly invented the process of making a glass tube airtight (a process in alchemy) using a secret seal.

Online Etymology Dictionary, © 2010 Douglas Harper

hermetic in Medicine




Completely sealed, especially against the escape or entry of air.
Related formsher•meti•cal•ly adv.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.