land yacht

noun2

1. •
   A vehicle used in land sailing, consisting of little more than a carriage and a sail.
2. •
   (informal) A long, heavy, luxurious automobile, providing a comfortable ride but poor handling characteristics.

   • A frequently cited example is a “land yacht” to describe an SUV: this blend creates a structure out of the ideas behind it, suggesting that the large car moves on the road like a yacht over water — 2013