inert

adj. lacking the power to move itself, inanimate; inactive, sedentary; sluggish, slow; neutral, having little or no chemical reaction (Chemistry)

In English, to be inert is to be in a state of doing little or nothing.In chemistry, the term inert is used to describe something that is not chemically active. The noble gases were described as being inert because they did not react with the other elements or themselves. It is now understood that the reason that inert gases are completely inert to basic chemical reactions (such as combustion, for example), is because their outer valence shell is completely filled with electrons. With a filled outer valence shell, an inert atom is not easily able to acquire or lose an electron, and is therefore not able to participate in any chemical reactions. For inert atoms or molecules, a lot of energy is involved before it can combine with other elements to form compounds. A high temperature and pressure is necessary, and sometimes requires the presence of a catalyst.
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Adjective
1. unable to move or resist motion
(similar) nonmoving, unmoving
2. having only a limited ability to react chemically; not active; "inert matter"; "an indifferent chemical in a reaction"
(synonym) indifferent, neutral
(similar) unreactive
(classification) chemistry, chemical science
3. slow and apathetic; "she was fat and inert"; "a sluggish worker"; "a mind grown torpid in old age"
(synonym) sluggish, torpid
(similar) inactive

adj. inert, inanimate, inactive

(a.)
Not having or manifesting active properties; not affecting other substances when brought in contact with them; powerless for an expected or desired effect.
  

(a.)
Indisposed to move or act; very slow to act; sluggish; dull; inactive; indolent; lifeless.
  

(a.)
Destitute of the power of moving itself, or of active resistance to motion; as, matter is inert.