To a very great degree; more than usual or expected.
From the adjective “extreme,” which came via Middle English from Old French, from Latin “extremus” meaning “outermost” or “utmost.” Over time, English added the -ly ending to turn it into an adverb describing intensity.
“Extremely” literally comes from a word about the farthest edge or outer limit. So when you say something is “extremely hot,” you’re saying it’s almost at the edge of what you can handle.
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