nau·​ti·​loid | \ ˈnȯ-tə-ˌlȯid How to pronounce nautiloid (audio) , ˈnä- \

Definition of nautiloid

: any of a subclass (Nautiloidea) of cephalopods bearing an external straight, curved, or spiral shell that were abundant chiefly in the Paleozoic but are represented in the recent fauna only by the nautiluses

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Other Words from nautiloid

nautiloid adjective

Examples of nautiloid in a Sentence

Recent Examples on the Web Reefs built by microbes gave way to some of the first coral reefs, trilobites grew larger, and tentacled predators such as nautiloids diversified and swarmed the mostly fishless seas. Joshua Sokol, Science | AAAS, "Veil of dust from ancient asteroid breakup may have cooled Earth," 18 Sep. 2019 Perhaps the smaller mosasaur caught the nautiloid, but was forced to give up its prey when a larger mosasaur approached. Brian Switek, WIRED, "Mosasaur Bites and Limpet Scrapes," 11 Apr. 2012

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'nautiloid.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of nautiloid

circa 1728, in the meaning defined above

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The first known use of nautiloid was circa 1728

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Cite this Entry

“Nautiloid.” Dictionary, Merriam-Webster, Accessed 30 Nov. 2020.

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