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early 15c., originally medical, "the darkening of a sore," from Latin obfuscationem (nominative obfuscatio), noun of action from past participle stem of obfuscare (see obfuscate).
1530s, from Latin obfuscatus, past participle of obfuscare "to darken," from ob "over" (see ob-) + fuscare "to make dark," from fuscus "dark" (see dusk). Related: Obfuscated; obfuscating.