Texas is the second most populous and the second most extensive of the 50 states in the United States of America, and the most extensive state of the 48 contiguous United States. The name, based on the Caddo word tejas meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in East Texas. Located in the South Central United States, Texas shares an international border with the Mexican states of Chihuahua, Coahuila, Nuevo León, and Tamaulipas to the south, and borders the US states of New Mexico to the west, Oklahoma to the north, Arkansas to the northeast, and Louisiana to the east. Texas has an area of 268,820 square miles (696,200 sq km), and a growing population of 25.7 million residents.