[1] : The Collaborative International Dictionary of English v.0.48

inertia \iner"tia\, n. l., idleness, fr. iners idle. see
   inert.
   1913 webster
   1. physics that property of matter by which it tends when
      at rest to remain so, and when in motion to continue in
      motion, and in the same straight line or direction, unless
      acted on by some external force; -- sometimes called vis
      inertiae. the inertia of a body is proportional to its
      mass.
      1913 webster +pjc

   2. inertness; indisposition to motion, exertion, or action;
      lack of energy; sluggishness.
      1913 webster

            men . . . have immense irresolution and inertia.
                                                  --carlyle.
      1913 webster

   3. med. lack of activity; sluggishness; -- said especially
      of the uterus, when, in labor, its contractions have
      nearly or wholly ceased.
      1913 webster

   center of inertia. mech. see under center.
      1913 webster
see also:
inert vis inertiae center of inertia center 

[2] : WordNet (r) 2.0

inertia
     n 1: a disposition to remain inactive or inert; "he had to
          overcome his inertia and get back to work" syn: inactiveness,
           inactivity ant: activeness
     2: physics the tendency of a body to maintain is state of
        rest or uniform motion unless acted upon by an external
        force
see also:
inactiveness inactivity activeness 

[3] : Moby Thesaurus II by Grady Ward, 1.0

112 moby thesaurus words for "inertia":
   a wise passiveness, abeyance, apathy, catalepsy, catatonia,
   cautiousness, circumspection, contemplation, contemplative life,
   creeping, deadliness, deathliness, deliberateness, deliberation,
   dilatoriness, do-nothing policy, do-nothingism, do-nothingness,
   dormancy, drawl, dullness, entropy, ergophobia, faineancy,
   faineantise, firmness, foot-dragging, hibernation, hoboism,
   idleness, immobility, immobilization, immovability, immovableness,
   inaction, inactiveness, inactivity, indifference, indolence,
   inertness, inexertion, inextricability, inflexibility,
   irremovability, just being, laggardness, laissez-aller,
   laissez-faire, laissez-faireism, languor, lassitude, latency,
   laziness, leisureliness, lentitude, lentor, listlessness,
   lotus-eating, lull, meditation, mere existence, mere tropism,
   motionlessness, neutralism, neutrality, neutralness,
   noninvolvement, nonparticipation, nonresistance, nonviolence,
   nonviolent resistance, pacifism, paralysis, passive resistance,
   passive self-annihilation, passiveness, passivism, passivity,
   pokiness, policy, procrastination, quiescence, quietism,
   reluctance, remissness, rigidity, shiftlessness, slackness, sloth,
   slothfulness, slowness, sluggardy, sluggishness, solidity,
   spring fever, stagnancy, stagnation, standpattism, stasis,
   suspense, suspension, tentativeness, torpor, underactivity,
   unmovability, unyieldingness, vagrancy, vegetation, vis inertiae,
   vita contemplativa, waiting game, watching and waiting

Inertia >> I Words
Inertia, definition of term: Inertia
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