inertia

noun
in·​er·​tia | \ i-ˈnər-shə How to pronounce inertia (audio) , -shē-ə\

Definition of inertia

1a : a property of matter by which it remains at rest or in uniform motion in the same straight line unless acted upon by some external force
b : an analogous property of other physical quantities (such as electricity)
2 : indisposition to motion, exertion, or change : inertness

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Other Words from inertia

inertial \ i-​ˈnər-​shəl How to pronounce inertial (audio) , -​shē-​əl \ adjective
inertially \ i-​ˈnər-​sh(ə-​)lē How to pronounce inertially (audio) \ adverb

Did You Know?

Inertia is the inherent property of a body that makes it oppose any force that would cause a change in its motion. A body at rest and a body in motion both oppose forces that might cause acceleration. The inertia of a body can be measured by its mass, which governs its resistance to the action of a force, or by its moment of inertia about a specified axis, which measures its resistance to the action of a torque about the same axiss.

Examples of inertia in a Sentence

He blames governmental inertia for the holdup. After 10 years in an unsatisfying job she overcame her inertia and went back to school.

Recent Examples on the Web

But the crassness of the gag is especially revealing in a movie that, in its imaginative poverty and emotional inertia, feels less like an adaptation of its predecessor than a betrayal. Los Angeles Times, "‘The Lion King’ is a huge hit. It might also be Disney’s most dispiriting remake yet," 22 July 2019 Yet the recording booth never knew any inertia, at least not when Ducky or Bunny took their turns at bat. Marc Snetiker, EW.com, "How Key and Peele turned Ducky and Bunny into Toy Story 4's biggest scene-stealers," 21 June 2019 Journalists like Colvin and Conroy in turn accepted the responsibility, bore witness, and tried to shake the West’s inertia. Muhammad Idrees Ahmad, The New York Review of Books, "How Assad Made Truth a Casualty of War," 7 Sep. 2018 No one knew it at the time, but there was another contributing factor: institutional inertia. John D'anna, azcentral, "For a while in 1983, sheets of plywood were all that kept the mighty Glen Canyon Dam from overflowing," 18 July 2019 Both call for persistent effort and a little planning to overcome inertia and set more passive activities aside for a while. Jim Higgins, Milwaukee Journal Sentinel, "How to read 35, 50 or 100 books a year: Give up on the boring ones," 18 July 2019 In those cases, the women’s stories, and the men’s, bolstered each other, fighting assumptions and inertias, making the individual claimants more and more difficult to dismiss. Megan Garber, The Atlantic, "The Cruel Paradox at the Heart of E. Jean Carroll’s Allegation Against Trump," 24 June 2019 Its products may still be used, but out of inertia. The Economist, "What open-source culture can teach tech titans and their critics," 18 July 2019 The Wood Island Life Saving Station very nearly forever disappeared into a fog of political inertia, swallowed by financial distress and imperiled by the collective shrug of municipal shoulders. Thomas Farragher, BostonGlobe.com, "A piece of Maine’s maritime history gets a lifeline," 10 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'inertia.' 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 inertia

1713, in the meaning defined at sense 1a

History and Etymology for inertia

New Latin, from Latin, lack of skill, from inert-, iners

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Statistics for inertia

Last Updated

2 Sep 2019

Look-up Popularity

Time Traveler for inertia

The first known use of inertia was in 1713

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More Definitions for inertia

inertia

noun

English Language Learners Definition of inertia

: lack of movement or activity especially when movement or activity is wanted or needed
: a feeling of not having the energy or desire that is needed to move, change, etc.
physics : a property of matter by which something that is not moving remains still and something that is moving goes at the same speed and in the same direction until another thing or force affects it

inertia

noun
in·​er·​tia | \ i-ˈnər-shə How to pronounce inertia (audio) \

Kids Definition of inertia

1 : a property of matter by which it remains at rest or in motion in the same straight line unless acted upon by some external force
2 : a tendency not to move or change He stayed at the job mostly because of his inertia.

inertia

noun
in·​er·​tia | \ in-ˈər-shə, -shē-ə How to pronounce inertia (audio) \

Medical Definition of inertia

1a : a property of matter by which it remains at rest or in uniform motion in the same straight line unless acted upon by some external force
b : an analogous property of other physical quantities (as electricity)
2 : lack of activity or movement used especially of the uterus in labor when its contractions are weak or irregular

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