bastard pimpernel vs false pimpernel

bastard pimpernel and false pimpernel both are nouns.

Word	Noun	Adjective	Verb	Adverb
bastard pimpernel	Yes	No	No	No
false pimpernel	Yes	No	No	No

As nouns, bastard pimpernel and false pimpernel are synonyms defined as:

bastard pimpernel and false pimpernel: weedy plant having short dry chafflike leaves

Other synonyms of bastard pimpernel include chaffweed.

bastard pimpernel (noun)	false pimpernel (noun)
weedy plant having short dry chafflike leaves	weedy plant having short dry chafflike leaves