1. A person from the northern United States, especially New England. In this context, the opposite could be:
* A Southerner: Someone from the southern United States.
* A Midwesterner: Someone from the Midwest.
* A Californian: Someone from California.
2. A northerner in general, especially during the American Civil War. This is a more historical context, and the opposite would be:
* A Rebel: Someone who fought for the Confederate States of America.
3. A member of the New York Yankees baseball team. In this case, the opposite would be:
* A fan of a different team: Someone who supports a rival team in Major League Baseball.
4. A colloquial term for an American. While not exactly "opposite", it's used to differentiate from other nationalities. In this case, the opposite could be:
* A foreigner: Someone who is not American.
Therefore, the "opposite" of Yankee depends heavily on the specific meaning and context.