Something that's unable to move or moving without much energy can be described as inert. Wind up in a body cast and you’ll find yourself not only itchy, but totally inert.

When motion is restricted or sluggish, or when something or someone appears lifeless, the adjective to use is inert. A dog who's playing dead is inert, as is a really boring movie. Or for those of you paying attention in chemistry class, you may have heard of inert gases — those elements that won't react with other elements or form chemical compounds.

Definitions of inert
  1. adjective
    unable to move or resist motion
    nonmoving, unmoving
    not in motion
  2. adjective
    slow and apathetic
    synonyms: sluggish, soggy, torpid
    not active physically or mentally
  3. adjective
    having only a limited ability to react chemically; chemically inactive
    inert matter”
    synonyms: indifferent, neutral
    (chemistry) not reacting chemically
Word Family

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