Photo Credit: ImmoLaos - an example of a single floor villa.
In English, the term villa can mean any varying size residence or property nowadays. Though it often refers to a secondary, vacation, or country property. The term is used more so in Europe and Australia than it is in North America.
Photo Credit: Rentsbuy - an example of 2 floor villa.
Photo Credit: Rentsbuy - a modern, Lao style home
By comparison, the western "villa" in Laos is often characterized as made entirely of concrete painted white, with colored tile roofing, exterior columns or pillars in the front, with the entire foundation of the home entirely on the ground. They're very easy to point out as you drive around any Lao city.