Spinus pinus vs pine siskin

Spinus pinus and pine siskin both are nouns.

Word	Noun	Adjective	Verb	Adverb
Spinus pinus	Yes	No	No	No
pine siskin	Yes	No	No	No

As nouns, Spinus pinus and pine siskin are synonyms defined as:

Spinus pinus and pine siskin: small finch of North American coniferous forests

Other synonyms of Spinus pinus include pine finch.

Spinus pinus (noun)	pine siskin (noun)
small finch of North American coniferous forests	small finch of North American coniferous forests