Gringo

Latin-American and Spanish slang for anyone of North American or British descent and dates from the mid-19th century. The story that it derives from the American marching song Green Grow the Rushes-O during the US-Mexican War (1846-48) is without substance. The most favoured origin is that it derives from the Spanish word griego meaning Greek, in the sense that all foreign languages sound like Greek to the Spanish. This etymology had already circulated in Spanish-language dictionaries for a century before the Mexican-American War.