The Collaborative International Dictionary of English v.0.48:

Swallowwort \Swal"low*wort`\, n. (Bot.)
      (a) See Celandine.
      (b) A poisonous plant (Vincetoxicum officinale) of the
          Milkweed family, at one time used in medicine; -- also
          called white swallowwort.
          [1913 Webster]

   African swallowwort, a plant of the genus Stapelia.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Celandine \Cel"an*dine\ (s[e^]l"[a^]n*d[imac]n), n. [OE.
   celidoine, OF. celidoine, F. ch['e]lidoine, fr. L. chelidonia
   (sc. herba), fr. chelidonius pertaining to the swallow, Gr.
   chelido`nios, fr. chelidw`n the swallow, akin to L. hirundo a
   swallow.] (Bot.)
   A perennial herbaceous plant (Chelidonium majus) of the
   poppy family, with yellow flowers. It is used as a medicine
   in jaundice, etc., and its acrid saffron-colored juice is
   used to cure warts and the itch; -- called also greater
   celandine and swallowwort.
   [1913 Webster]

   Lasser celandine, the pilewort (Ranunculus Ficaria).
      [1913 Webster]

WordNet (r) 3.0 (2006):

swallowwort
    n 1: tropical herb having orange-red flowers followed by pods
         suggesting a swallow with outspread wings; a weed
         throughout the tropics [syn: blood flower, swallowwort,
         Asclepias curassavica]
    2: perennial herb with branched woody stock and bright yellow
       flowers [syn: celandine, greater celandine,
       swallowwort, swallow wort, Chelidonium majus]