pterodactyl vs flying reptile

pterodactyl and flying reptile both are nouns.

Word	Noun	Adjective	Verb	Adverb
pterodactyl	Yes	No	No	No
flying reptile	Yes	No	No	No

As nouns, flying reptile is a hypernym of pterodactyl; that is, flying reptile is a word with a broader meaning than pterodactyl:

pterodactyl: extinct flying reptile
flying reptile: an extinct reptile of the Jurassic and Cretaceous having a bird-like beak and membranous wings supported by the very long fourth digit of each forelimb

Other hypernyms of pterodactyl include pterosaur.

pterodactyl (noun)	flying reptile (noun)
extinct flying reptile	an extinct reptile of the Jurassic and Cretaceous having a bird-like beak and membranous wings supported by the very long fourth digit of each forelimb