Synonyms for Chaste (same or very similar meaning)
WordNet sense 1 (not elaborate or elaborated; simple):
plain
WordNet sense 2 (concerned with principles of right and wrong or conforming to standards of behavior and character based on those principles):
moral
WordNet sense 3 (in a state of sexual virginity):
pure, virtuous
WordNet sense 4 (abstaining from sexual intercourse):
continent
From the ODE community, based on WordNet
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