While "goodnight" is a common way to bid someone farewell, it's not necessarily the most formal or culturally specific choice in Spanish-speaking countries. In many Latin American countries, people tend to use "a buenas noches" (ah bwehnahs noh-chehs) instead, which literally means "good nights." This phrase is more commonly used than "goodnight," especially in regions like Mexico, Argentina, and Chile. In contrast, some people may use "buenas noches" (bweh-nahs noh-chehs), which means "good evenings." This phrase is more suitable for bidding someone farewell at the end of a meal or a evening activity, rather than in general. If you want to impress your Spanish friend, learning these variations will show that you're making an effort to understand local customs and nuances.