western poison oak vs Toxicodendron diversilobum

western poison oak and Toxicodendron diversilobum both are nouns.

Word	Noun	Adjective	Verb	Adverb
western poison oak	Yes	No	No	No
Toxicodendron diversilobum	Yes	No	No	No

As nouns, western poison oak and Toxicodendron diversilobum are synonyms defined as:

western poison oak and Toxicodendron diversilobum: poisonous shrub of the Pacific coast of North America that causes a rash on contact

Other synonyms of western poison oak include Rhus diversiloba.

western poison oak (noun)	Toxicodendron diversilobum (noun)
poisonous shrub of the Pacific coast of North America that causes a rash on contact	poisonous shrub of the Pacific coast of North America that causes a rash on contact