- 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.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for nautiloid
He referred also to the nautiloid shell of the larva falling to one side.
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
Cephalic shield pointed behind; shell internal, chiefly membranous, with calcified nucleus, nautiloid; parapodia forming fins.
- 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
- 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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