inert
adj.not moving or not having the power to move. In science, it describes a gas or substance that does not react with other chemicals.
adj.lacking the ability or strength to move; chemically inactive. Often describes substances that do not undergo chemical reactions under a set of given conditions.
“Helium is an inert gas.”
“The patient lay inert on the bed while the doctors performed their final checks before the procedure.”
“While the noble gases are famously inert, modern chemistry has demonstrated that even they can be forced into compounds under extreme laboratory conditions of pressure and temperature.”
Often used predicatively after linking verbs like 'remain' or 'lie'.
“Most things humans produced could be disposed of into the environment: Stone, brick and glass are inert; paper and wood biodegrade; most metals will rust away.”
“She said it was important to remember that “soil is not an inert material.”
From French inerte, from Latin iners (“inactive, inert”).
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.