While a commonly used slang term for Americans used by Mexicans, gringo is used throughout Latin America to refer to Americans. It isn't inherently negative, but in some regions - especially Puerto Rico - gringo often is used to refer to white Americans, and many times in a derogatory fashion.

In Mexico proper, "Gringo" can have a derogatory, or casual/ non pejorative meaning depending on the context of which it is delivered. "Gabacho" has more insulting connotations. A commonly held myth within the environs of Mexico itself is that the origin of "Gringo" was an allusion as to the U.S. Army under the commands of generals Taylor/Scott fielding green coloured uniforms, hence the "Green-Go!!!" silliness. (This is utter rubbish, as any serious student of the Mexican-American War knows that it was the colour blue, and remained so till khaki, and later, onward thence to green, replaced it many decades later. A popular song commonly sung by the intrepid American troops, whilst they marched along was, "Green Grow the Rushes," these words being repeated (refrained) throughout the song, "Green grow,..etc," being taken by (the then) contemporary Mexican ear as "gringo." (The most "likely" origin...) In other regions, apart from Mexico itself, it basically refers to any "european looking" individual.

a gringo is just a north american or anglo-saxon. it is usually a white person but doesnt have to be. it isnt a hateful term but it can be used hatefully. it also represents behaviour and attitudes latinos consider to be "american".

Term used by Latin Americans to talk about an American, it doesnt matter the color of his skin

Contrary to some things that have been posted here, the US did not wear green coats, or green uniforms, during the Mexican American War, so that explanation for the origin of this word is bogus.

But the term is indeed related to American soldiers who invaded Mexico during the Mexican-American war. It actually came from the lines of what was then a song that was very popular with American infantrymen.

See the example.

1.-In Monterrey, Mexico, we use the word "gringo" for people who were born in the US.
It has nothing to do with race. It's not derogative.It's a nationality.
If someone says "pinche gringo" the derogative word is "pinche", not "gringo".
We call them gringos because it'd be stupid to call them "americans", since America is a continent, not a country.

2.- Something from the US

Gringo is a word used mostly by spanish speakers to define an anglo-saxon person, depending the connotation it can be offensive, neutral or even friendly. Also the meaning can change depending on the people that uses it.

For example in Mexico and central America is mostly used in an insultive way.
In Argentina due that most people has italian and spanian roots (white and brown hair) it's merely to describe someone that's anglo-saxon or very white and blonde, due to many "Gringos" that went to live to Argentina.

1. A person from the USA.

2. A tourist in Mexico with the stereotype of northern European race.

3. In Mexico, common nickname to a person with pale skin, Brown or blond hair and blue/green eyes.

PERIOD

The word originated in Mexico, when the United States of America invaded Mexico in order to appropiate half of its territory, back on mid 19th century. Of course this action against "peace and freedom" is not in elementary school textbooks in USA, but it is in any other serious document about USA history.

American soldiers entered the country through the Gulf of Mexico, taking down the main port of Veracruz and then heading towards Mexico City. The troops were wearing GREEN COATS.

Mexican people along the way from Veracruz to Mexico suffered the advance of the enemy and many battles were fought. However, the American army finally reached Mexico City and took the city down in an epic battle still remembered by all the Mexicans: The battle of Chapultepec Castle. This palace, in the top of a hill, is the highest point over Mexico City: there was the Mexican flag, so it was a symbolic target.

The headquarters of the Military College were in Chapultepec castle too, and when the "green coats" were climbing the hill, a few young cadets refused to leave and decided to defend the castle to death. Then, when the battle was helplessly lost, one of the cadets took the Mexican flag, wrapped himself on it and jumped off the cliff were the castle is set, dying in the rocks below, thus avoiding the American army to take the flag. When the American commander saw the corpses of the cadets, he said in amazement "They are only children!". So they became in death Los Niños Héroes, the symbol in Mexico of the resistance against invaders: the American army... the green coats.

The war was over and USA claimed half of Mexico's territory... then the green coats went home, having gained possesion of Texas and other territories -and their resources- (the same old motif than nowadys, but the speech has changed).

Ever since, the relationtship USA-Mexico has developed into a very complex love-hate relationtship and the destiny of both nations is linked together, but back then, a new term was born in popular language: gringo (green coat)

Now, let's make clear that the term is used nowadays the same as affectionate as pejorative and as none of the above too. As complex as it seems, Mexican people can use the word with different intentions but in any case with just one meaning: it refers in a common way to USA citizens, who are distinctive not because of the colour of their skin, but because of their culture and behavior (anyone outside USA knows exactly what behavior is it!)

Other derivatives of the word include:

gringa: female for gringo, as substantive.

gringo/gringa: as adjectives.

agringado: something/someone that resembles USA culture or the American way of life.

Gringolandia: U.S.A.

As a final note i must say that the word spread to other countries over Latin America (even to Spain) where it is used to refer to foreigners and/or white people: but that's just the way some people outside Mexico understand the word!

Nevertheless, in Mexico, a "gringo" is just an American citizen. And it implies nothing else.
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