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Orthoceras

noun
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Or·​thoc·​er·​as | \ ȯ(r)ˈthäsərəs \

Definition of Orthoceras

: an ill-defined genus of extinct nautiloid cephalopod mollusks having a long tapering shell that is nearly or quite straight, almost smooth, and many-chambered

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History and Etymology for Orthoceras

New Latin, from orth- + -ceras

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Cite this Entry

“Orthoceras.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Orthoceras. Accessed 20 Jan. 2021.

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