unenlightened has 2 distinct synonyms spread across 1 of its 2 senses. Each sense below keeps its own list, because a synonym belongs to a meaning and not to a word: swapping one sense's substitute into another sense's sentence is how a thesaurus makes writing worse. Its one recorded opposite is enlightened.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
not enlightened; ignorant
“the devices by which unenlightened men preserved the unjust social order”
lacking information or instruction
“lamentably unenlightened as to the laws”
Synonyms, antonyms and the broader and narrower relations for unenlightened come from Princeton University’s WordNet. Full sources and licences.