a mollusk of the subclass Nautiloidea, including nautiluses and many fossil species that were abundant in the Ordovician and Silurian periods.
noting or pertaining to a nautiloid.
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How to use nautiloid in a sentence
Cephalic shield pointed behind; shell internal, chiefly membranous, with calcified nucleus, nautiloid; parapodia forming fins.
The remarkable group of the Trilobites had precedence in order of time of the nautiloid shell-fishes.The Chain of Life in Geological Time | Sir J. William Dawson
He referred also to the nautiloid shell of the larva falling to one side.
British Dictionary definitions for nautiloid
any mollusc of the Nautiloidea, a group of cephalopods that includes the pearly nautilus and many extinct forms
of, relating to, or belonging to the Nautiloidea
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Scientific definitions for nautiloid
Any of various cephalopod mollusks of the subclass Nautiloidea, having a straight or coiled shell divided internally into a series of chambers of increasing size connected by a central tube. The nautiloids include the modern nautiluses as well as numerous extinct species dating back as far as the Cambrian Period.
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