Uruguay means in guaraní language "río de los caracoles" (river of snails), this words is composed by: uruguá (winkle or snail) and y ('water' or 'river'). Neverthelss, some authors say that Uruguay means "river of colorful birds" or "river of painted birds.

In a book (travel notes) i am reading about South America, the author says that -as Oscar said- guay means "river" and para means "this side" in Guarani language. So as far as i understand, Paraguay means "this side of the river". So i expect the meaning of Uruguay to be something related to this.

guay = cool Well, both come from guaraní language. Both take the name from a river and I think in guaraní "guai" means "river".