Amphibious vehicle and Motor vehicle

Amphibious vehicle noun - A flat-bottomed motor vehicle that can travel on land or water.

Motor vehicle and amphibious vehicle are semantically related. In some cases you can use "Motor vehicle" instead a noun phrase "Amphibious vehicle".

Motor vehicle noun - A self-propelled passenger vehicle on four wheels.

Amphibious vehicle and motor vehicle are semantically related. Sometimes you can replace phrase "Amphibious vehicle" with "Motor vehicle", this phrases are similar.