myna bird vs grackle

myna bird and grackle both are nouns.

Word	Noun	Adjective	Verb	Adverb
myna bird	Yes	No	No	No
grackle	Yes	No	No	No

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

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

myna bird (noun)	grackle (noun)
tropical Asian starlings	long-tailed American blackbird having iridescent black plumage
	glossy black Asiatic starling often taught to mimic speech