Having no rival; better than any possible competitor(adjective)
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Use "unrivalled" in a sentence
"O keen-witted being, the seventh daughter of Angiras is known by the name of Mahamati, who is always present at sacrifices of great splendour, and that worshipful daughter of Angiras, whom they call unrivalled and without portion, and about whom people utter the words kuhu kuhu wonder, is known by the name of Kuhu. '"
"Long may you maintain unrivalled dominion at home and abroad; and long may your husbands rue the hour when first they made you promise "to obey"!"
"The press freedom watchdog, Reporters sans frontières (RSF), ranks Lebanese media 66th out of 173 nations in its press freedom index, but notes that the press has a level of expression unrivalled in the region."