plural noun Se·la·chii \-kēˌī\

Definition of Selachii

in some classifications

  1. :  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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capable of being understood in two ways

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