mynah bird vs hill myna

mynah bird and hill myna both are nouns.

Word	Noun	Adjective	Verb	Adverb
mynah bird	Yes	No	No	No
hill myna	Yes	No	No	No

As nouns, hill myna is a hyponym of mynah bird; that is, hill myna is a word with a more specific, narrower meaning than mynah bird:

Other hyponyms of mynah bird include Acridotheres tristis, crested myna, grackle, Gracula religiosa, Indian grackle.

mynah bird (noun)	hill myna (noun)
tropical Asian starlings	glossy black Asiatic starling often taught to mimic speech