Source : Webster's Revised Unabridged Dictionary (1913)

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}.

   {African swallowwort}, a plant of the genus Stapelia.

Source : WordNet®

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}, {Asclepias
          curassavica}]
     2: perennial herb with branched woody stock and bright yellow
        flowers [syn: {celandine}, {greater celandine}, {swallow
        wort}, {Chelidonium majus}]