Simple Definition of inertia
: 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
Full Definition of inertia
1 a : 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 (as electricity)
2 : indisposition to motion, exertion, or change : inertness
Examples of inertia
He blames governmental inertia for the holdup.
After 10 years in an unsatisfying job she overcame her inertia and went back to school.
Origin of inertia
New Latin, from Latin, lack of skill, from inert-, iners
First Known Use: 1713
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
Learn More about inertia
Thesaurus: All synonyms and antonyms for "inertia" Medical Dictionary: Definition of "inertia" Spanish Central: Translation of "inertia" Nglish: Translation of "inertia" for Spanish speakers Britannica English: Translation of "inertia" for Arabic speakers Britannica.com: Encyclopedia article about "inertia"
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