"Downstater" is a term used to describe someone who lives in the southern part of a state, particularly in New York. However, there are a number of synonyms that can be used to describe someone from this region. One option is "southerner," which is a more general term that refers to people from the southern part of a country or state. "Lowlander" is another option, which specifically refers to someone from a lowland region. "Shore dweller" can also be used to describe someone who lives near the coast. Other potential synonyms for "downstater" might include "southern resident," "bottom dweller," or even "red-stater," depending on the context and the speaker's preference.