cockleburr vs cocklebur

cockleburr and cocklebur both are nouns.

Word	Noun	Adjective	Verb	Adverb
cockleburr	Yes	No	No	No
cocklebur	Yes	No	No	No

As nouns, cockleburr and cocklebur are synonyms defined as:

cockleburr and cocklebur: any coarse weed of the genus Xanthium having spiny burrs

Other synonyms of cockleburr include cockle-bur, cockle-burr.

cockleburr (noun)	cocklebur (noun)
any coarse weed of the genus Xanthium having spiny burrs	any coarse weed of the genus Xanthium having spiny burrs
	burdock having heart-shaped leaves found in open woodland, hedgerows and rough grassland of Europe (except extreme N) and Asia Minor; sometimes cultivated for medicinal and culinary use