merle vs European blackbird

merle and European blackbird both are nouns.

Word	Noun	Adjective	Verb	Adverb
merle	Yes	No	No	No
European blackbird	Yes	No	No	No

As nouns, merle and European blackbird are synonyms defined as:

Other synonyms of merle include blackbird, merl, ousel, ouzel, Turdus merula.

merle (noun)	European blackbird (noun)
common black European thrush	common black European thrush