inertia

noun

in·​er·​tia i-ˈnər-shə How to pronounce inertia (audio)
-shē-ə
1
a
: 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
inertial
i-ˈnər-shəl How to pronounce inertia (audio)
-shē-əl
adjective
inertially 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 axis.

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 subsequent growth of the country’s nuclear arsenal was mainly the result of inertia on the part of the military-industrial complex. Niall Ferguson, Foreign Affairs, 20 Feb. 2024 If frequency imbalances grow, the second line of defense is either speeding up or slowing down the already-spinning turbines in the plants – a process called inertia – to generate more electricity and fill the frequency imbalance. Elizabeth Weise, USA TODAY, 27 Jan. 2024 This aversion to such a progressive approach uncovers a disconcerting preference for sentimental longing over realistic solutions, favoring inertia and decay over dynamic revitalization. Reader Commentary, Baltimore Sun, 19 Jan. 2024 That doesn’t mean that the policy wasn’t adopted, through inertia and the Biden administration’s unilateral imposition of a de facto open border for a large swath of asylum seekers. Rich Lowry, National Review, 10 Dec. 2023 After years of investigative inertia, the information Las Vegas police compiled arrived all but gift-wrapped. John L. Smith, Rolling Stone, 25 Jan. 2024 In medicine, inertia can be a strangely powerful force, but Virginia Apgar never succumbed to it. Amos Grünebaum, STAT, 23 Jan. 2024 The mysteriousness of Khaled’s inertia, his woundedness—both a literal wound and a figurative one—turns Matar’s narrative into a deep and detailed exploration not so much of abandonment as of self-abandonment. James Wood, The New Yorker, 15 Jan. 2024 Still, the lack of a constitution meant institutional inertia. Jordan Castro, Harper's Magazine, 9 Jan. 2024 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'inertia.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

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

First Known Use

1713, in the meaning defined at sense 1a

Time Traveler
The first known use of inertia was in 1713

Dictionary Entries Near inertia

Cite this Entry

“Inertia.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/inertia. Accessed 2 Mar. 2024.

Kids Definition

inertia

noun
in·​er·​tia in-ˈər-shə How to pronounce inertia (audio)
-shē-ə
1
: a property of matter by which it remains at rest or in unchanging motion unless acted on by some external force
2
: a tendency not to move or change
inertial adjective

Medical Definition

inertia

noun
in·​er·​tia in-ˈər-shə, -shē-ə How to pronounce inertia (audio)
1
a
: 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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