Perambulator

n.
  1. One who perambulates.
  2. A surveyor's instrument for measuring distances. It consists of a wheel arranged to roll along over the ground, with an apparatus of clockwork, and a dial plate upon which the distance traveled is shown by an index. See Odometer.
  3. A low carriage for a child, propelled by pushing; a baby carriage; -- called also pram, in Britain.