Definition of Selachii
in some classifications
: a variously delimited group of elasmobranch fishes: a : a primary division of Pisces that includes all the elasmobranchs and is equivalent to Chondrichthyes b : a class or subclass that includes all the elasmobranchs except the chimaeras c : a subclass or order that includes the existing sharks and rays as distinguished from the extinct Pleuropterygii and Ichthyotomi d : a suborder that includes the existing sharks as distinguished from the rays and is equivalent to Pleurotremata
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Origin and Etymology of selachii
New Latin, irregular from selachos cartilaginous fish; akin to Greek selas light, brightness — more at selen-
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