silkweed vs milkweed

silkweed and milkweed both are nouns.

Word	Noun	Adjective	Verb	Adverb
silkweed	Yes	No	No	No
milkweed	Yes	No	No	No

As nouns, silkweed and milkweed are synonyms defined as:

silkweed and milkweed: any of numerous plants of the genus Asclepias having milky juice and pods that split open releasing seeds with downy tufts

silkweed (noun)	milkweed (noun)
any of numerous plants of the genus Asclepias having milky juice and pods that split open releasing seeds with downy tufts	any of numerous plants of the genus Asclepias having milky juice and pods that split open releasing seeds with downy tufts
	annual Eurasian sow thistle with soft spiny leaves and rayed yellow flower heads