hermetic
hur-MET-ik
/hɜːrˈmɛtɪk/
Completely airtight or impervious to external influence.
Implies a physical seal so perfect that no gas, moisture, or microorganisms can pass through in either direction.
The story behind the word. Alchemists were obsessed with sealing vessels so perfectly that no volatile spirits could escape during their transmutations. They credited the invention of a magical airtight seal to Hermes Trismegistus, the patron of their craft. Over the centuries, this alchemical 'seal of Hermes' evolved into our modern word for any airtight closure.
Word relationships
- airtight: Airtight is the common, everyday equivalent, while hermetic is preferred in scientific, technical, and historical contexts.
- impermeable: Impermeable refers to a material's property of not letting fluids pass, whereas hermetic refers to the complete integrity of a seal or system.
- porous: Porous materials contain tiny holes that allow fluids or gases to pass through easily.
- leaky: Leaky implies a failure in a seal or container that allows substances to escape or enter.
Commonly confused with
- aerobic: Aerobic refers to organisms or processes that require oxygen, whereas hermetic seals are designed to exclude oxygen entirely.
Word family
- hermetically (adverb): In an airtight manner.
- hermeticism (noun): An ancient occult tradition, unrelated to packaging but sharing the same root.
Collocations
- hermetic seal
- hermetically sealed
- hermetic closure
- hermetic packaging
Example sentences
- "The tin can is a hermetic container which prevents the entry of microorganisms and oxygen, ensuring the food remains safe for years." Food preservation textbook
Memory hook
Think of 'Hermes' the messenger god sealing a secret letter so tightly that even air cannot leak out. Hermetic means sealed so tight, not even air can take flight.
When not to use
Do not use to describe temporary or loose closures, like a standard zip-lock bag, which allows micro-gases to pass over time.
Fun facts
- The term 'hermetically sealed' was originally used in the 17th century to describe glass tubes used in thermometers.
Related words
Explore more words
opaque, authentic, self-contained, transcendent, impregnable, holistic
Also appears in
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