Oldenburg is a word that typically refers to a city in Germany or a breed of horse. When it comes to synonyms for Oldenburg, there are a few different options depending on the context. For example, if you are talking about the city, you might use the synonyms "Oldenburg in Holstein" or "Oldenburg in Ostfriesland", which are two other cities in Germany that share the same name. Alternatively, if you are talking about the breed of horse, you might use the synonym "Hanoverian", which is another breed that is similar in appearance and history. Overall, while there aren't many direct synonyms for Oldenburg, there are plenty of related terms that can be used depending on the context.