To tangle or complicate something, or to untangle and clarify something (the word has opposite meanings depending on context).
From Middle Dutch ravel or Old Dutch ravelen. Interestingly, 'unravel' and 'ravel' both mean to untangle, creating one of English's famous contradonyms.
Maurice Ravel, the famous composer, may have been named after this word, and his music actually embodies its duality—surfaces seem simple but tangle into complex, intricate harmonic webs.
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