Superlative form of curt; most brief, abrupt, or rudely concise in speech or manner.
From curt (from Latin curtus, 'short') plus the superlative suffix -est. The form appears in Early Modern English when comparison of curt adjectives was necessary.
The word 'curt' has an interesting reputation—it literally means short, but when applied to speech it implies rudeness, which shows how speakers conflate brevity with dismissiveness!
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