Cyanocitta cristata vs blue jay

Cyanocitta cristata and blue jay both are nouns.

Word	Noun	Adjective	Verb	Adverb
Cyanocitta cristata	Yes	No	No	No
blue jay	Yes	No	No	No

As nouns, Cyanocitta cristata and blue jay are synonyms defined as:

Cyanocitta cristata and blue jay: common jay of eastern North America; bright blue with grey breast

Other synonyms of Cyanocitta cristata include jaybird.

Cyanocitta cristata (noun)	blue jay (noun)
common jay of eastern North America; bright blue with grey breast	common jay of eastern North America; bright blue with grey breast