cockle-bur vs cockleburr

cockle-bur and cockleburr both are nouns.

Word	Noun	Adjective	Verb	Adverb
cockle-bur	Yes	No	No	No
cockleburr	Yes	No	No	No

As nouns, cockle-bur and cockleburr are synonyms defined as:

cockle-bur and cockleburr: any coarse weed of the genus Xanthium having spiny burrs

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

cockle-bur (noun)	cockleburr (noun)
any coarse weed of the genus Xanthium having spiny burrs	any coarse weed of the genus Xanthium having spiny burrs