Superlative form of extreme; the greatest degree of intensity, distance from center, or radical nature.
From extreme + -est (superlative suffix). Old English comparative/superlative ending system, though modern English prefers 'most extreme' for this multi-syllabic adjective.
Shakespeare used 'extremest' regularly ('the extremest kindness'), but modern English style prefers 'most extreme'—it's a shift that happened because longer adjectives just sound smoother with 'most' than with '-est!'
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