: 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

Word History


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

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Dictionary Entries Near Hesperornis

Cite this Entry

“Hesperornis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Hesperornis. Accessed 29 May. 2023.

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