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inertia

[ in-ur-shuh, ih-nur- ]
/ ɪnˈɜr ʃə, ɪˈnɜr- /
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noun
inertness, especially with regard to effort, motion, action, and the like; inactivity; sluggishness.
Physics.
  1. the property of matter by which it retains its state of rest or its velocity along a straight line so long as it is not acted upon by an external force.
  2. an analogous property of a force: electric inertia.
Medicine/Medical. lack of activity, especially as applied to a uterus during childbirth when its contractions have decreased or stopped.
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Origin of inertia

1705–15; <Latin: lack of skill, slothfulness. See inert, -ia

OTHER WORDS FROM inertia

in·er·tial, adjectivenon·i·ner·tial, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use inertia in a sentence

British Dictionary definitions for inertia

inertia
/ (ɪnˈɜːʃə, -ʃɪə) /

noun
the state of being inert; disinclination to move or act
physics
  1. the tendency of a body to preserve its state of rest or uniform motion unless acted upon by an external force
  2. an analogous property of other physical quantities that resist changethermal inertia

Derived forms of inertia

inertial, adjective
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for inertia

inertia
[ ĭ-nûrshə ]

The resistance of a body to changes in its momentum. Because of inertia, a body at rest remains at rest, and a body in motion continues moving in a straight line and at a constant speed, unless a force is applied to it. Mass can be considered a measure of a body's inertia. See more at Newton's laws of motion. See also mass.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for inertia

inertia
[ (i-nur-shuh) ]

In physics, the tendency for objects at rest to remain at rest, and for objects in uniform motion to continue in motion in a straight line, unless acted on by an outside force. (See Newton's laws of motion.)

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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