inert
Americanadjective
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having no inherent power of action, motion, or resistance (active ).
inert matter.
- Synonyms:
- motionless, lifeless, unmoving, immobile
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Chemistry. having little or no ability to react, as nitrogen that occurs uncombined in the atmosphere.
-
Pharmacology. having no pharmacological action, as the excipient of a pill.
-
inactive or sluggish by habit or nature.
adjective
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having no inherent ability to move or to resist motion
-
inactive, lazy, or sluggish
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having only a limited ability to react chemically; unreactive
Related Words
See inactive.
Other Word Forms
- inertly adverb
- inertness noun
- noninert adjective
- noninertly adverb
- noninertness noun
- uninert adjective
- uninertly adverb
Etymology
Origin of inert
First recorded in 1640–50; from Latin inert- (stem of iners ) “unskillful,” equivalent to in- in- 3 + -ert-, combining form of art- (stem of ars ) “skill”; art 1
Explanation
Something that's unable to move or moving without much energy can be described as inert. Wind up in a body cast and you’ll find yourself not only itchy, but totally inert. When motion is restricted or sluggish, or when something or someone appears lifeless, the adjective to use is inert. A dog who's playing dead is inert, as is a really boring movie. Or for those of you paying attention in chemistry class, you may have heard of inert gases — those elements that won't react with other elements or form chemical compounds.
Vocabulary lists containing inert
Anti-Antonyms: Words Without Opposites
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Languor Management: Synonyms for "Lazy"
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And Then There Were None
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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.
In “Two Prosecutors,” the inert nobodies blocking Kornev’s progress are crisply choreographed, Stalin’s existential choke hold strangling their very spirit.
From Los Angeles Times • Mar. 26, 2026
Lutnick’s testimony this past week, like Bondi’s, is thus operating as a still life in what happens when the law becomes inert.
From Slate • Feb. 12, 2026
At first glance, the moon appears lifeless and inert.
From Science Daily • Jan. 5, 2026
It’s a salad that can sit in the fridge for days without losing its snap, yet it’s never inert: a forkful zings, a little sweet, a little tart, a little green, a little peppery.
From Salon • Dec. 18, 2025
Pull myself to my knees, muscles numb and inert.
From "Without Refuge" by Jane Mitchell
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.
