inertia

noun
in·​er·​tia | \i-ˈnər-shə, -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 , -​shē-​əl \ adjective
inertially \ i-​ˈnər-​sh(ə-​)lē \ 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

There was one person, notably, who resisted those inertias: Helen herself. Megan Garber, The Atlantic, "#PlaneBae and the Slow Death of Whimsy," 6 July 2018 Most advocacy groups are trying to be patient, chalking the delays up to the inevitable inertia of a giant bureaucracy forced to change. New York Times, "Ban Was Lifted, but Transgender Recruits Still Can’t Join Up," 5 July 2018 All the inertia that has hit reigning champions in the past. SI.com, "World Cup Daily Podcast: Germany Crashes Out of the World Cup," 27 June 2018 Afterward, the franchise had been ground to dust during the listless inertia of the Manny Acta irrelevancy. Bill Livingston, cleveland.com, "Cleveland Indians' two 'Tito's' and their lives in baseball -- Bill Livingston," 16 Feb. 2018 This inertia leaves one other possibility that is becoming increasingly likely: starvation. New York Times, "Let Mountain Lions Eat Horses," 12 May 2018 There are still hurdles, including years of inertia and competing congressional priorities. Nate Poppino, idahostatesman, "Nuclear tests gave these Idahoans cancer, they say. Will Congress support them now?," 27 June 2018 But most linger on, shielded by bureaucratic inertia, lack of resources or sympathetic judges. Bojan Pancevski, WSJ, "Immigration Backlash Erodes Merkel’s Power in Conservative Stronghold," 26 June 2018 Rose Byrne, Chris O'Dowd and Ethan Hawke form an unlikely triangle together by inertia, pop culture obsessiveness and heartache. Kate Stanhope, latimes.com, "Critics' Picks: 10 films to see this summer," 26 Apr. 2018

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

28 Oct 2018

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 \

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 \

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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