What is "guayra"

Guayrá was a historical region of the Spanish Empire, located in the Governorate of the Río de la Plata, within the colonial Viceroyalty of Peru. The region is located in present day Paraguay and Paraná.

There are some conflicting etymologies for the origin of the name, with some claiming it was named after a cacique of the region whose name was Guayrá or Guayracá. Alternatively, the word might come from Guarani "kwa y ra" ("can not pass", "impassable") or even "guay ra" ("river that goes [beyond]").