plural noun

in some classifications
: a variously delimited group of elasmobranch fishes:
: a primary division of Pisces that includes all the elasmobranchs and is equivalent to Chondrichthyes
: a class or subclass that includes all the elasmobranchs except the chimaeras
: a subclass or order that includes the existing sharks and rays as distinguished from the extinct Pleuropterygii and Ichthyotomi
: a suborder that includes the existing sharks as distinguished from the rays and is equivalent to Pleurotremata

Word History


New Latin, irregular from selachos cartilaginous fish; akin to Greek selas light, brightness

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Dictionary Entries Near Selachii

Cite this Entry

“Selachii.” Dictionary, Merriam-Webster, Accessed 22 Sep. 2023.

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