The superlative form of dismal; the most gloomy, depressing, or bleak.
From dismal + -est (superlative suffix). This archaic superlative form was more common in Middle English but has been largely replaced by 'most dismal' in modern usage.
Modern English prefers 'most dismal' over 'dismalest,' showing how English is slowly dropping old -est superlatives on longer words—it's language taking the easier route over time.
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