Thuja occidentalis vs American arborvitae

Thuja occidentalis and American arborvitae both are nouns.

Word	Noun	Adjective	Verb	Adverb
Thuja occidentalis	Yes	No	No	No
American arborvitae	Yes	No	No	No

As nouns, Thuja occidentalis and American arborvitae are synonyms defined as:

Thuja occidentalis and American arborvitae: small evergreen of eastern North America having tiny scalelike leaves on flattened branchlets

Other synonyms of Thuja occidentalis include northern white cedar, white cedar.

Thuja occidentalis (noun)	American arborvitae (noun)
small evergreen of eastern North America having tiny scalelike leaves on flattened branchlets	small evergreen of eastern North America having tiny scalelike leaves on flattened branchlets