The Collaborative International Dictionary of English v.0.48:

Rocambole \Roc"am*bole\, n. [F.] [Written also rokambole.]
   (Bot.)
   A name of Allium Scorodoprasum and Allium Ascalonium, two
   kinds of garlic, the latter of which is also called
   shallot.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Allium scorodoprasum
    n 1: European leek cultivated and used like leeks [syn: sand
         leek, giant garlic, Spanish garlic, rocambole,
         Allium scorodoprasum]