Synonyms for Settled (same or very similar meaning)
WordNet sense 1 (determined or decided upon as by an authority):
determined
WordNet sense 2 (settled securely and unconditionally):
established
WordNet sense 3 (inhabited by colonists):
colonised, colonized
WordNet sense 4 (clearly defined):
defined, formed
WordNet sense 5 ((of weather) free from storm or wind):
calm
From the ODE community, based on WordNet
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