In*ac"tive (?), a. [Pref. in- not + active: cf. F. inactif.]
Not active; having no power to move; that does not or can not produce results; inert; as, matter is, of itself, inactive.
Not disposed to action or effort; not diligent or industrious; not busy; idle; as, an inactive officer.
3. Chem. & Opt.
Not active; inert; esp., not exhibiting any action or activity on polarized light; optically neutral; -- said of isomeric forms of certain substances, in distinction from other forms which are optically active; as, racemic acid is an inactive tartaric acid.
Syn. -- Inert; dull; sluggish; idle; indolent; slothful; lazy. See Inert.
© Webster 1913.