Crex crex vs corncrake

Crex crex and corncrake both are nouns.

Word	Noun	Adjective	Verb	Adverb
Crex crex	Yes	No	No	No
corncrake	Yes	No	No	No

As nouns, Crex crex and corncrake are synonyms defined as:

Crex crex and corncrake: common Eurasian rail that frequents grain fields

Other synonyms of Crex crex include land rail.

Crex crex (noun)	corncrake (noun)
common Eurasian rail that frequents grain fields	common Eurasian rail that frequents grain fields