\Man`ga*nese"\, n. [F. mangan[`e]se, It. manganese,
sasso magnesio; prob. corrupted from L. magnes, because of
its resemblance to the magnet. See {Magnet}, and cf.
{Magnesia}.] (Chem.)
An element obtained by reduction of its oxide, as a hard,
grayish white metal, fusible with difficulty, but easily
oxidized. Its ores occur abundantly in nature as the minerals
pyrolusite, manganite, etc. Symbol Mn. Atomic weight 54.8.
Note: An alloy of manganese with iron (called ferromanganese)
      is used to increase the density and hardness of steel.
{Black oxide of manganese}, {Manganese dioxide or peroxide},
   or {Black manganese} (Chem.), a heavy black powder {MnO2},
   occurring native as the mineral pyrolusite, and valuable
   as a strong oxidizer; -- called also familiarly
   {manganese}. It colors glass violet, and is used as a
   decolorizer to remove the green tint of impure glass.
{Manganese bronze}, an alloy made by adding from one to two
   per cent of manganese to the copper and zinc used in
   brass.