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noun Uncommon

inertia

ihn-UR-shuh

Inertia (noun) means In physics, the tendency of an object to keep doing whatever it's already doing — staying still or moving in a straight line — unless a force acts on it. Example: “Passengers lurch forward when a bus brakes suddenly because of inertia.”

noun
1
In physics, the tendency of an object to keep doing whatever it's already doing — staying still or moving in a straight line — unless a force acts on it.
"Passengers lurch forward when a bus brakes suddenly because of inertia."
"The heavier the object, the more inertia it has to overcome to start moving."
2
A reluctance to act, change, or get started; sluggishness.
"Sheer inertia kept him in the same job for twenty years."

How to Use Inertia

Learner’s notes

In plain EnglishResistance to change — an object resisting a change in motion, or a person resisting getting off the sofa.

Common pairings
overcome inertia the force of inertia bureaucratic inertia

Word Forms

inertias plural, inertiae plural, inertiæ plural

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Can you complete this real example?

Passengers lurch forward when a bus brakes suddenly because of _____.

Etymology

From Latin inertia, "lack of skill, inactivity," from iners — in- + ars, "skill." The physics sense was introduced by the astronomer Johannes Kepler.

Origin: Latin

inactivity inactiveness

Related Words

Rhymes for inertia

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Frequently Asked Questions

What does “inertia” mean?

The word “inertia” means in physics, the tendency of an object to keep doing whatever it's already doing — staying still or moving in a straight line — unless a force acts on it. In plain terms, resistance to change — an object resisting a change in motion, or a person resisting getting off the sofa.

How do you pronounce “inertia”?

“Inertia” is pronounced ihn-UR-shuh (/ɪnˈɝ.ʃə/ in IPA).

How do you use “inertia” in a sentence?

Here is “inertia” used in a sentence: “Passengers lurch forward when a bus brakes suddenly because of inertia.”

What part of speech is “inertia”?

“Inertia” is a noun.

Where does the word “inertia” come from?

The word “inertia” comes from Latin. From Latin inertia, "lack of skill, inactivity," from iners — in- + ars, "skill." The physics sense was introduced by the astronomer Johannes Kepler.

Is “inertia” a common word?

“Inertia” is an uncommon word in modern English.

How many meanings does “inertia” have?

“Inertia” has 2 distinct senses listed in this dictionary. The most common is: in physics, the tendency of an object to keep doing whatever it's already doing — staying still or moving in a straight line — unless a force acts on it.

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