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undetected

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adjective un·de·tect·ed \ˌən-di-ˈtek-təd, -dē-\

Definition of undetected

: not observed, noticed, or detected an undetected flaw/error an undetected illness These rare mistakes are subtle and may go undetected for months and even years. — Mario Salvadori

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First Known Use of undetected

circa 1602

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