#amphibious_vehicle__amphibian  a flat-bottomed motor vehicle that can travel on land or water
  supertype:  motor_vehicle__motorvehicle__automotive_vehicle  a self-propelled wheeled vehicle that does not run on rails
  subtype:  swamp_buggy__swampbuggy__marsh_buggy__marshbuggy  an amphibious vehicle typically having four-wheel drive and a raised body

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