milkweed vs silkweed

milkweed and silkweed both are nouns.

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

As nouns, milkweed and silkweed are synonyms defined as:

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

milkweed (noun)	silkweed (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