Synonyms for Swallowwort (same or very similar meaning)
WordNet sense 1 (tropical herb having orange-red flowers followed by pods suggesting a swallow with outspread wings; a weed throughout the tropics):
blood flower, Asclepias curassavica
WordNet sense 2 (perennial herb with branched woody stock and bright yellow flowers):
celandine, Chelidonium majus, greater celandine
From the ODE community, based on WordNet
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