\Re*gen"er*a`tor\ (-?`t?r), n.
1. One who, or that which, regenerates.
2. (Mech.) A device used in connection with hot-air engines,
   gas-burning furnaces, etc., in which the incoming air or
   gas is heated by being brought into contact with masses of
   iron, brick, etc., which have been previously heated by
   the outgoing, or escaping, hot air or gas.