nau·​ti·​loid ˈnȯ-tə-ˌlȯid How to pronounce nautiloid (audio)
: 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
nautiloid adjective

Example Sentences

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, 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, 11 Apr. 2012

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'nautiloid.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

circa 1728, in the meaning defined above

Time Traveler
The first known use of nautiloid was circa 1728

Dictionary Entries Near nautiloid

Cite this Entry

“Nautiloid.” Dictionary, Merriam-Webster, Accessed 30 May. 2023.

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