true frog vs anuran

true frog and anuran both are nouns.

Word	Noun	Adjective	Verb	Adverb
true frog	Yes	No	No	No
anuran	Yes	Yes	No	No

As nouns, anuran is a hypernym of true frog; that is, anuran is a word with a broader meaning than true frog:

true frog: insectivorous usually semiaquatic web-footed amphibian with smooth moist skin and long hind legs
anuran: any of various tailless stout-bodied amphibians with long hind limbs for leaping; semiaquatic and terrestrial species

Other hypernyms of true frog include batrachian, frog, salientian, toad, toad frog.

true frog (noun)	anuran (noun)
insectivorous usually semiaquatic web-footed amphibian with smooth moist skin and long hind legs	any of various tailless stout-bodied amphibians with long hind limbs for leaping; semiaquatic and terrestrial species

true frog (adjective)	anuran (adjective)
	relating to frogs and toads