Orthoceras

noun 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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Origin and Etymology of orthoceras

New Latin, from orth- + -ceras


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