In the UK motorhomes are typically referred to as a motorhome, however, the term Campervan or Camper is used in other parts of the world. Occasionally the term motorhome can be separated into motor home, likewise Camper van.
The nationality or location of the person typically determines the phrase used, so if someone was holidaying from Australia to England, they may look for a Camper hire in England, or those from Italy may prefer London Campervan rental.
People in America prefer the term RV, which is short for Recreational Vehicle. To add even more confusion to the mix, the phrase Campervan is widely used to reference a VW Campervan. You can see why Just go stick to the term motorhome!