lion cub vs Panthera leo

lion cub and Panthera leo both are nouns.

Word	Noun	Adjective	Verb	Adverb
lion cub	Yes	No	No	No
Panthera leo	Yes	No	No	No

As nouns, Panthera leo is a hypernym of lion cub; that is, Panthera leo is a word with a broader meaning than lion cub:

lion cub: a young lion
Panthera leo: large gregarious predatory feline of Africa and India having a tawny coat with a shaggy mane in the male

Other hypernyms of lion cub include cub, young carnivore, king of beasts, lion.

lion cub (noun)	Panthera leo (noun)
a young lion	large gregarious predatory feline of Africa and India having a tawny coat with a shaggy mane in the male