The superlative form of 'blind'; most lacking in sight, vision, or understanding.
From Old English 'blind' (unable to see) plus the superlative suffix '-est.' This is a regular superlative formation that has existed in English for over a thousand years, comparing the degree of blindness.
Superlatives like 'blindest' are interesting because they can refer to literal vision loss, but also to emotional blindness—'the blindest rage' or 'blindest love.' English lets us use physical descriptions to talk about mental and emotional states in poetic ways.
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