The Collaborative International Dictionary of English v.0.48:

Sesban \Ses"ban\, n. [F., fr. Ar. saisab[=a]n, seiseb[=a]n, a
   kind of tree, fr. Per. s[imac]sab[=a]n seed of cinquefoil.]
   (Bot.)
   A leguminous shrub (Sesbania aculeata) which furnishes a
   fiber used for making ropes.
   [1913 Webster]

   Note: The name is applied also to the similar plant,
         Sesbania Aegyptiaca, and other species of the same
         genus.
         [1913 Webster]