inertia

[ in-ur-shuh, ih-nur- ]
/ ɪnˈɜr ʃə, ɪˈnɜr- /

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.

Origin of inertia

1705–15; < Latin: lack of skill, slothfulness. See inert, -ia
Related formsin·er·tial, adjectivenon·i·ner·tial, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for inertia

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 Formsinertial, 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

Word Origin and History for inertia

inertia


n.

1713, introduced as a term in physics 17c. by German astronomer and physician Johann Kepler (1571-1630), from Latin inertia "unskillfulness, idleness," from iners (genitive inertis) "unskilled, inactive;" see inert. Used in Modern Latin by Newton (1687). Sense of "apathy" first recorded 1822.

Online Etymology Dictionary, © 2010 Douglas Harper

Medicine definitions for inertia

inertia

[ ĭ-nûrshə ]

n.

The tendency of a body to resist acceleration; the tendency of a body at rest to remain at rest or of a body in motion to stay in motion in a straight line unless acted on by an outside force.
Resistance or disinclination to motion, action, or change.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Science 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.

Culture 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.