cuckoo flower vs ragged robin

cuckoo flower and ragged robin both are nouns.

Word	Noun	Adjective	Verb	Adverb
cuckoo flower	Yes	No	No	No
ragged robin	Yes	No	No	No

As nouns, cuckoo flower and ragged robin are synonyms defined as:

cuckoo flower and ragged robin: common perennial native to Europe and western Asia having usually pink flowers with ragged petals

Other synonyms of cuckoo flower include Lychins floscuculi, Lychnis flos-cuculi.

cuckoo flower (noun)	ragged robin (noun)
common perennial native to Europe and western Asia having usually pink flowers with ragged petals	common perennial native to Europe and western Asia having usually pink flowers with ragged petals
a bitter cress of Europe and America