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 The cost challenge To move, a vehicle has to resist three forces: drag, or resistance from the wind; friction from the road; and inertia, or resistance to a change in speed. Shashank Sripad, The Conversation, "Better batteries are fueling a surge of electric scooters in India and China," 28 Oct. 2019 The cost challenge To move, a vehicle has to resist three forces: drag, or resistance from the wind; friction from the road; and inertia, or resistance to a change in speed. Shashank Sripad, Quartz India, "The key to an electric scooter revolution in India is getting the battery right," 28 Oct. 2019 Attributing it to inertia, boredom, or technology is a lightweight cop-out, not to mention that all of those are just screens for deeper issues. Nathaniel Friedman, The New Republic, "Moments Without Truth," 21 Oct. 2019 The relatively small tax burden of the super-rich is the product of decades of choices made by American lawmakers, some deliberate, others the result of indecisiveness or inertia, Saez and Zucman say. oregonlive, "U.S. billionaires paid lower tax rate than working class last year, researchers say," 9 Oct. 2019 Even with children who struggle socially or are prone to inertia, parental focus still belongs on ethics, manners and self-care; pushing toward achievement is about the parent, not the child. Carolyn Hax, The Mercury News, "Carolyn Hax: He won’t tell me who’s talking trash about me," 26 July 2019 Even with children who struggle socially or are prone to inertia, parental focus still belongs on ethics, manners and self-care; pushing toward achievement is about the parent, not the child. Carolyn Hax, Detroit Free Press, "Mom worries about pushing daughter too hard," 26 July 2019 Even with children who struggle socially or are prone to inertia, parental focus still belongs on ethics, manners and self-care; pushing toward achievement is about the parent, not the child. Washington Post, "Carolyn Hax: A potential tiger mom wants to change her stripes," 26 July 2019 Even with children who struggle socially or are prone to inertia, parental focus still belongs on ethics, manners and self-care; pushing toward achievement is about the parent, not the child. Carolyn Hax, al, "Carolyn Hax: Question your assumptions when you find yourself too invested in your child’s achievements," 25 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

11 Nov 2019

Time Traveler for inertia

The first known use of inertia was in 1713

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More Definitions for inertia

inertia

noun
How to pronounce inertia (audio)

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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