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 forceb : an analogous property of other physical quantities (such as electricity)
2 : indisposition to motion, exertion, or change : inertness
inertialplay \i-ˈnər-shəl, -shē-əl\ adjective
inertiallyplay \i-ˈnər-sh(ə-)lē\ adverb
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 of inertia from the Web
Part of the work of the next few decades is to imagine and build a better future rather than letting inertia reign.
But with so many others pushing in the same direction as Overstock, this inertia may eventually give way.
Finally, the issue of inertia – the force that pushes you back in your seat during acceleration – had to be resolved.
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.
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.
Origin and Etymology of inertia
New Latin, from Latin, lack of skill, from inert-, iners
First Known Use: 1713
INERTIA Defined for English Language Learners
Definition of inertia for English Language Learners
: 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 Defined for Kids
Definition of inertia for Students
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.
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 forceb: 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
Seen and Heard
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