from The American Heritage® Dictionary of the English Language, 5th Edition.

  • adjective Incapable of moving or acting.
  • adjective Sluggish in action or motion; lethargic. synonym: inactive.
  • adjective Chemistry Not readily reactive with other elements; forming few or no chemical compounds.
  • adjective Having no pharmacologic, metabolic, or other physiological effect.

from The Century Dictionary.

  • Having no inherent power of action, motion, or resistance; without inherent force; inanimate; lifeless: applied to matter in its intrinsic character: as, an inert mass of clay; an inert corpse.
  • Indisposed or unable to move or act; inactive; sluggish: as, an inert drug.

from the GNU version of the Collaborative International Dictionary of English.

  • adjective Destitute of the power of moving itself, or of active resistance to motion.
  • adjective Indisposed to move or act; very slow to act; sluggish; dull; inactive; indolent; lifeless.
  • adjective Not having or manifesting active properties; not affecting other substances when brought in contact with them; powerless for an expected or desired effect.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • adjective Unable to move or act; inanimate.
  • adjective Sluggish or lethargic.
  • adjective In chemistry, not readily reacting with other elements or compounds.
  • adjective Having no therapeutic action.
  • noun chemistry A substance that does not react chemically.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • adjective slow and apathetic
  • adjective unable to move or resist motion
  • adjective having only a limited ability to react chemically; chemically inactive


from The American Heritage® Dictionary of the English Language, 4th Edition

[Latin iners, inert- : in-, not; see in– + ars, skill; see ar- in Indo-European roots.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

From French inerte, from Latin iners ("inactive, inert").


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  • Merck said small pieces of the shrink wrap, which it called an "inert carbon material," can stick to the inside of product vials and turn brown during the sterilization process.

    Shrink Wrap Found in Merck Vaccines Peter Loftus 2011

  • And what we know as inert matter, this is only the result of death in individuals, it is the dead bodies of individuals decomposed and resmelted between the hammer and anvil, fire and sand of the sun and the moon.

    Fantasia of the Unconscious 1907

  • Potential intelligence, like potential, can remain inert forever.

    You Can Do Anything You Put Your Mind To: A Noble Lie?, Bryan Caplan | EconLog | Library of Economics and Liberty 2009

  • Yet Shield limps out of the gate, inert from the first frame and devoid of suspense. 2009

  • If you took away just one proton, you would have flourine, a gas which, far from being inert, is highly reactive and dangerous.

    Archive 2006-04-23 Edward Willett 2006

  • If you took away just one proton, you would have flourine, a gas which, far from being inert, is highly reactive and dangerous.

    The first paragraph I wrote today was... Edward Willett 2006

  • As a chemical kineticist and photochemist, I knew that such a molecule could not remain inert in the atmosphere forever, if only because solar photochemistry at high altitudes would break it down.

    F.Sherwood Rowland - Autobiography 1996

  • A reaction induced on the laboratory bench may, like yeast in inert dough, leaven the whole of mankind, lightening and lifting it to heights undreamed of by its ancestors.

    The Contribution of Creative Chemistry to the Humanities 1957

  • After a long time, Secotan, who had lain inert where he had been thrown into the boat, got to his knees and took up the second paddle.

    The Windy Hill 1922

  • a certain form of exertion and action, -- I shall grant, of course, that nothing whatever that exists is in that sense inert; but I shall affirm that you use the word inert in quite a different sense from the usual one.

    The Recreations of a Country Parson Andrew Kennedy Hutchison Boyd 1862


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  • A nerd is never inert.

    September 28, 2008