selachian /sɪˈleɪkɪən/adjective 2noun 1forms 3 adjective2 •Pertaining to (what is now classified as) the superorder Selachimorpha or division Selachii, comprising the sharks; or, sometimes more broadly, to the subclass Elasmobranchii, including sharks, rays and related species.Fig. 4-10 shows crude apparatus which was used to make rough measurements of the vertical forces produced by selachian tails. — 1981 •Sharklike.These two tours had whetted the colonies' appetite for Royal visits, and by the turn of the century that appetite was positively selachian. — 1963 noun1 •Any organism of the superorder Selachimorpha or subclass Elasmobranchii; an extant shark (or related species).However, some selachians enter freshwater and a few, like the stingray Paratrygon motoro, are even restricted to freshwater. — 1999 formsselachians · more selachian · most selachian
