villero

Villa = Shanty town ... "marginal" or informal settlements are units of irregular, low-cost dwellings, usually on lands belonging to third parties, and most often located on the periphery of cities. These dwellings are often assembled from pieces of plywood, corrugated metal, sheets of plastic, and any other material that will provide cover.

Villero = someone that lives in a villa

Its used to insult someone as a synonym of disgusting