Four-wheeler and Taxis

Four-wheeler noun - A hackney carriage with four wheels.

Taxis and four-wheeler are semantically related In some cases you can use "Taxis" instead a noun phrase "Four-wheeler".

Taxis noun - A locomotor response toward or away from an external stimulus by a motile (and usually simple) organism.

Four-wheeler and taxis are semantically related in car topic. Sometimes you can use "Four-wheeler" instead a noun "Taxis".