a. Incapable of moving or acting: "[Some patients] lingered, unable to breathe on their own, inert and unresponsive even to the most noxious stimulus" (Gary Greenberg).
b. Sluggish in action or motion; lethargic. See Synonyms at inactive.
2. Chemistry Not readily reactive with other elements; forming few or no chemical compounds.
3. Having no pharmacologic, metabolic, or other physiological effect.
[Latin iners, inert- : in-, not; see IN-1 + ars, skill; see ar- in the Appendix of Indo-European roots.]
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