"Dobar dan" (pronounced "dough-bar Dan") is a greeting in Serbo-Croatian. Well... Actually let's get back to "dobar dan" in a minute.
Serbo-Croatian is not technically a language. It is rather a family of languages that includes Bosnian, Croatian, Montenegrin, and Serbian. These languages are considered to be ausbauspraches, which in practice means that they are basically different dialects of the same language. While there is some measure of debate on this, those who have lived in the area tell me that the main difference between the two titular languages—Serbian and Croatian—is that Serbian uses the Cyrillic alphabet (AKA the Russian alphabet), whereas Croatian uses the Latin alphabet (AKA the Roman or English alphabet, although it has been slightly expanded for Croatian). However, it is also said that Serbian uses both alphabets, so I suppose this is not a hard-and-fast rule.
"Dobar dan"—meaning "good day"—is the same in Serbian and Croatian (and presumably Montenegrin). One source lists "zdravo" as the equivalent greeting in Bosnian, but other sources say that "zdravo" is the Serbian word for "hello" (as opposed to "good day"), so I. My guess is that the Serbian Cyrillic version of the word would be "добар дан". This seems to be confirmed by the previously cited reference.
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