Russian cactus vs Russian tumbleweed

Russian cactus and Russian tumbleweed both are nouns.

Word	Noun	Adjective	Verb	Adverb
Russian cactus	Yes	No	No	No
Russian tumbleweed	Yes	No	No	No

As nouns, Russian cactus and Russian tumbleweed are synonyms defined as:

Russian cactus and Russian tumbleweed: prickly bushy Eurasian plant; a troublesome weed in central and western United States

Other synonyms of Russian cactus include Russian thistle, Salsola kali tenuifolia, tumbleweed.

Russian cactus (noun)	Russian tumbleweed (noun)
prickly bushy Eurasian plant; a troublesome weed in central and western United States	prickly bushy Eurasian plant; a troublesome weed in central and western United States