llano (n.) Look up llano at Dictionary.com
1610s, American Spanish, "prairie; treeless, level plain," especially that of South America north of the Amazon, from noun use of Spanish llano "plain, even, level, smooth," ultimately from Latin planus "smooth, flat, level" (from PIE root *pele- (2) "flat; to spread"). Hence llanero "Latin-American cowboy" (1819), literally "plainsman."