biforine

from The Collaborative International Dictionary of English v.0.48
Biforine \Bif"o*rine\, n. [L. biforis, biforus, having two
   doors; bis twice + foris door.] (Bot.)
   An oval sac or cell, found in the leaves of certain plants of
   the order {Arace[ae]}. It has an opening at each end through
   which raphides, generated inside, are discharged.
   [1913 Webster]
    

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