Indian rhubarb vs Himalayan rhubarb

Indian rhubarb and Himalayan rhubarb both are nouns.

Word	Noun	Adjective	Verb	Adverb
Indian rhubarb	Yes	No	No	No
Himalayan rhubarb	Yes	No	No	No

As nouns, Indian rhubarb and Himalayan rhubarb are synonyms defined as:

Other synonyms of Indian rhubarb include red-veined pie plant, Rheum australe, Rheum emodi.

Indian rhubarb (noun)	Himalayan rhubarb (noun)
rhizomatous perennial herb with large dramatic peltate leaves and white to bright pink flowers in round heads on leafless stems; colonizes stream banks in the Sierra Nevada in California	Asian herb (Himalayas)
Asian herb (Himalayas)