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Synonyms for Unworldly (same or very similar meaning)

WordNet sense 1 (concerned with or affecting the spirit or soul):
spiritual, unearthly

WordNet sense 2 (not wise in the ways of the world):

WordNet sense 3 (marked by or showing unaffected simplicity and lack of guile or worldly experience):
naif, naive

From the ODE community, based on WordNetadd/edit