To make benighted; to plunge into darkness or ignorance; a rare variant of benight.
A variant or alternative form of benight, with the -en suffix sometimes added to verbs. This form is extremely rare and barely documented in English.
Benighten is like a word that English considered using but then decided against—it's technically constructed correctly but so rarely used that it's practically invisible in the language, showing how some potential words never catch on.
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