noun Hes·per·or·nis \ˌhespəˈrȯrnə̇s\

Definition of Hesperornis

  1. :  a genus of swimming birds (order Hesperornithiformes) from the Cretaceous of Kansas that resemble loons in form, that have teeth in each jaw implanted in a long groove, and that in some cases exceed five feet in length

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Origin and Etymology of hesperornis

New Latin, from Greek hesperos western + New Latin -ornis

Seen and Heard

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feeling or affected by lethargy

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