Plural of duello; multiple formal dueling systems or instances of ritualized combat.
Standard English plural of duello, formed by adding the -s suffix to the Italian loanword.
You rarely see 'duellos' in English because dueling was outlawed or died out, so we don't need a plural form much—it's a word stuck in historical amber, like 'blacksmith's tools' when nobody's blacksmithing anymore.
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