I. ˌ ̷ ̷ ̷ ̷ˌ ̷ ̷təˈrijēə noun plural
Usage: capitalized
Etymology: New Latin, from ichthy- + Greek pterygia, plural of pterygion fin
in some classifications : a subclass of fossil aquatic reptiles occurring from the late Carboniferous through the Jurassic and including the small freshwater Mesosauria and the extremely ichthyoid Ichthyosauria
II.
Etymology: New Latin, from ichthy- + Greek pterygia
synonym of ichthyosauria