Definition of inertia in English:

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Pronunciation: /ɪˈnəːʃə/


[mass noun]
1A tendency to do nothing or to remain unchanged: the bureaucratic inertia of the various tiers of government
More example sentences
  • Ignorance, fear, inertia, and stubbornness remain to be overcome.
  • Under current policy there is too much latitude for force structure decisions based on personal whim, the prevailing fashion or as default decisions arising out of bureaucratic compromise or inertia.
  • But whatever the smart individuals inside these organizations might think, bureaucratic inertia is killing those golden-egg geese.
inactivity, inaction, inactiveness, inertness, passivity, apathy, accidie, malaise, stagnation, dullness, enervation, sluggishness, lethargy, languor, languidness, listlessness, torpor, torpidity, idleness, indolence, laziness, sloth, slothfulness;
motionlessness, immobility, lifelessness
French archaic fainéance
rare stasis, otiosity, hebetude
2 Physics A property of matter by which it continues in its existing state of rest or uniform motion in a straight line, unless that state is changed by an external force: the power required to overcome friction and the inertia of the moving parts See also moment of inertia.
More example sentences
  • A better way to measure the mass of a microscopic sample is to quantify the sample's inertia as it is forced into motion.
  • Unlike Galileo, Newton insisted that the law of inertia applied only to motion in a straight line, not circular motion.
  • How fast and in what order remains to be seen, but the direction is a matter of inertia without friction.
2.1 [with modifier] Resistance to change in some other physical property: the thermal inertia of the oceans will delay the full rise in temperature for a few decades
More example sentences
  • The relatively large mass and thermal inertia of female desert tortoises usually prevents winter activity but facilitates their relaxed homeostasis.
  • Soil for the grass over the common room adds to the thermal inertia of the whole.
  • A heavy body weight is a disincentive for movement and physical activity, creating ‘movement inertia.’



Example sentences
  • The doors close as soon as Jewel is clear, and the inertialess transport quickly jets away from the building, circling around the city center and out over the desert.
  • The mirror surface of the ball doubles as a solar collector, and everything, the radio control, the laser, targeting, gyros, inertialess drive, all run off the battery.
  • A simple inertialess quasi-real-time microwave holographic recording system is described and preliminary results are presented.


Early 18th century (in sense 2): from Latin, from iners, inert- (see inert).

Words that rhyme with inertia

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