in·​ert | \i-ˈnərt \

Definition of inert 

1 : lacking the power to move

2 : very slow to move or act : sluggish

3 : deficient in active properties especially : lacking a usual or anticipated chemical or biological action

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Other Words from inert

inert noun
inertly adverb
inertness noun

Synonyms & Antonyms for inert


dull, inactive, lethargic, quiescent, sleepy, sluggish, torpid



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Choose the Right Synonym for inert

inactive, idle, inert, passive, supine mean not engaged in work or activity. inactive applies to anyone or anything not in action or in operation or at work. on inactive status as an astronaut inactive accounts idle applies to persons that are not busy or occupied or to their powers or their implements. workers were idle in the fields inert as applied to things implies powerlessness to move or to affect other things; as applied to persons it suggests an inherent or habitual indisposition to activity. inert ingredients in drugs an inert citizenry passive implies immobility or lack of normally expected response to an external force or influence and often suggests deliberate submissiveness or self-control. passive resistance supine applies only to persons and commonly implies abjectness or indolence. a supine willingness to play the fool

Examples of inert in a Sentence

an inert and lifeless body How does he propose to stimulate the inert economy and create jobs?

Recent Examples on the Web

The floating modules are made of an inert growing medium called coconut coir, made from coconut husks, which is rolled into tubes bound together with plastic mesh and frames of stainless steel. Patrick M. O'connell,, "A 'wild mile' on the Chicago River? It might be closer than you think," 22 June 2018 For Vincent Lindon, cast and bearded as the great man in this inert biopic from Jacques Doillon, that task entails gazing intently at statues, busts and naked models, looking gruff and serious, while the camera avoids close-ups of the detailing. Ben Kenigsberg, New York Times, "Review: ‘Rodin,’ a Biopic Heavy as Stone," 31 May 2018 That data is not just stashed away as inert ones and zeroes. Sandra Upson, WIRED, "Westworld Recap, Season 2 Episode 10: What Is Real?," 25 June 2018 But the bounty of talent counts for little in a tedious, inert piece that awkwardly shoehorns numerous dance interludes into a thin storyline. Frank Scheck, The Hollywood Reporter, "'The Beast in the Jungle': Theater Review," 24 May 2018 This jabbed a finger at the most inert bit: a square in which the last original statue was installed five centuries earlier. The Economist, "When Jeff Koons met Michelangelo," 19 Apr. 2018 But the heavy use of spy tropes only emphasizes how inert and uninvolving the tale is. New York Times, "Review: ‘Radio Delirio’ Focuses on a Forgettable Man," 17 June 2018 Yet shares of other device stocks were mostly inert in Monday trading, which could present an opportunity for investors. Charley Grant, WSJ, "Stryker Offer May Trigger Billions in Deal Making," 11 June 2018 The charcoal which is left is very inert and easily preserved. Anna Diamond, Smithsonian, "What Is the Future of Fire?," 25 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'inert.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of inert

1647, in the meaning defined at sense 1

History and Etymology for inert

Latin inert-, iners unskilled, idle, from in- + art-, ars skill — more at arm

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Dictionary Entries near inert



in error



inert gas


Statistics for inert

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Time Traveler for inert

The first known use of inert was in 1647

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More Definitions for inert



English Language Learners Definition of inert

: unable to move

: moving or acting very slowly

chemistry : not able to affect other chemicals when in contact with them : not chemically reactive


in·​ert | \i-ˈnərt \

Kids Definition of inert

: unable or slow to move or react inert gas

Other Words from inert

inertness noun


in·​ert | \in-ˈərt \

Medical Definition of inert 

1 : lacking the power to move

2 : deficient in active properties especially : lacking a usual or anticipated chemical or biological action an inert drug

Other Words from inert

inertness noun

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Comments on inert

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playful or foolish behavior

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