An·​cy·​loc·​er·​as | \ ˌansəˈläsərəs\

Definition of Ancyloceras

: a genus of ammonoids having a partly uncoiled shell and the aperture of the living chamber directed toward the coiled part

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First Known Use of Ancyloceras

1842, in the meaning defined above

History and Etymology for Ancyloceras

New Latin, from ankyl- + -ceras

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The first known use of Ancyloceras was in 1842

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formidable, illustrious, or eminent

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