Synonyms for Preliterate (same or very similar meaning)
WordNet sense 1 (not able to read or write):
illiterate
WordNet sense 2 (used of a society that has not developed writing):
nonliterate
WordNet sense 3 (not having a high state of culture and social development):
noncivilised, noncivilized
From the ODE community, based on WordNet
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