Hes·​per·​or·​nis | \ ˌhespəˈrȯrnə̇s\

Definition of Hesperornis

: 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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History and Etymology for Hesperornis

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

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to corrupt or become corrupted

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