Aythya ferina vs pochard

Aythya ferina and pochard both are nouns.

Word	Noun	Adjective	Verb	Adverb
Aythya ferina	Yes	No	No	No
pochard	Yes	No	No	No

As nouns, Aythya ferina and pochard are synonyms defined as:

Aythya ferina and pochard: heavy-bodied Old World diving duck having a grey-and-black body and reddish head

Aythya ferina (noun)	pochard (noun)
heavy-bodied Old World diving duck having a grey-and-black body and reddish head	heavy-bodied Old World diving duck having a grey-and-black body and reddish head