As nouns,
crocodilian reptile is a hypernym of
Gavialis gangeticus; that is, crocodilian reptile is a
word with a broader meaning than Gavialis gangeticus:
Gavialis gangeticus: large fish-eating Indian crocodilian with a long slender snout
crocodilian reptile: extant archosaurian reptile
Other hypernyms of Gavialis gangeticus include
crocodilian.