blackbird vs grackle

blackbird and grackle both are nouns.

Word	Noun	Adjective	Verb	Adverb
blackbird	Yes	No	No	No
grackle	Yes	No	No	No

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

blackbird: any bird of the family Icteridae whose male is black or predominantly black
grackle: long-tailed American blackbird having iridescent black plumage

blackbird (noun)	grackle (noun)
any bird of the family Icteridae whose male is black or predominantly black	long-tailed American blackbird having iridescent black plumage
common black European thrush	glossy black Asiatic starling often taught to mimic speech