What is denoting a person or thing conceived or spoken of indefinitely; a certain. "I am the sister of one Claudio" [Shak.], that is, of a certain man named Claudio called?

one — Denoting a person or thing conceived or spoken of indefinitely; a certain. "I am the sister of one Claudio" [Shak.], that is, of a certain man named Claudio. (Webster's 1913.)

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