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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Merriam-Webster unabridged
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Time Traveler for inertia
The first known use of inertia was in 1713
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