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adjective in·ert \i-ˈnərt\

Simple Definition of inert

  • : unable to move

  • : moving or acting very slowly

  • chemistry : not able to affect other chemicals when in contact with them : not chemically reactive

Full Definition of inert

  1. 1 :  lacking the power to move

  2. 2 :  very slow to move or act :  sluggish

  3. 3 :  deficient in active properties; especially :  lacking a usual or anticipated chemical or biological action

inert noun
in·ert·ly adverb
in·ert·ness noun

Examples of inert

  1. an inert and lifeless body

  2. How does he propose to stimulate the inert economy and create jobs?

Origin of inert

Latin inert-, iners unskilled, idle, from in- + art-, ars skill — more at arm

First Known Use: 1647

Synonym Discussion of inert

inactive, idle, inert, passive, supine mean not engaged in work or activity. inactive applies to anyone or anything not in action or in operation or at work <on inactive status as an astronaut> <inactive accounts>. idle applies to persons that are not busy or occupied or to their powers or their implements <workers were idle in the fields>. inert as applied to things implies powerlessness to move or to affect other things; as applied to persons it suggests an inherent or habitual indisposition to activity <inert ingredients in drugs> <an inert citizenry>. passive implies immobility or lack of normally expected response to an external force or influence and often suggests deliberate submissiveness or self-control <passive resistance>. supine applies only to persons and commonly implies abjectness or indolence <a supine willingness to play the fool>.

Other Chemical Engineering Terms

Medical Dictionary


adjective in·ert \in-ˈərt\

Medical Definition of inert

  1. 1:  lacking the power to move

  2. 2:  deficient in active properties; especially :  lacking a usual or anticipated chemical or biological action <an inert drug>

  3. in·ert·ness noun

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February 7, 2016

a slight offense

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