An insubstantial thing or person.
Early 19th century; earliest use found in Lord Byron (1788–1824), poet. From classical Latin nōminis umbra, literally ‘the shadow of a name’ from nōminis, genitive of nōmen + umbra shade, shadow.
nominis umbra/ˌnɒmɪnɪs ˈʌmbrə/ /ˌnəʊmɪnɪs ˈʌmbrə/
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