/ˌsɛləˈkoʊɪd/ Sə-lə-KOY-id

Definitions

1. noun

a type of extinct fish, specifically the order Selachimorpha, a group of fossilized sharks and rays, and also the family of modern spiny dogfish

“The fossil remains of ancient selachoids were discovered in the underwater excavation site.”

2. adjective

relating to or resembling sharks or rays

“The selachoid features of the ancient marine reptile are still being studied by paleontologists.”