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Webster 1913 Edition
Milkweed
Milk′weedˊ
,Noun.
(Bot.)
Any plant of the genera
Asclepias
and Acerates
, abounding in a milky juice, and having its seed attached to a long silky down; silkweed. The name is also applied to several other plants with a milky juice, as to several kinds of spurge. Its leaves are a favorite food source for the larvae of the monarch butterfly.