Synonyms for Southwestern (same or very similar meaning)
WordNet sense 1 (a dialect of Middle English):
West Saxon
WordNet sense 2 (situated in or oriented toward the southwest):
southwest, southwesterly
WordNet sense 3 (situated in or facing or moving toward or coming from the south):
south
WordNet sense 4 (of or characteristic of regions of the United States west of the Mississippi River):
western
From the ODE community, based on WordNet
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