Source : Webster's Revised Unabridged Dictionary (1913)

Legume \Leg"ume\ (l[e^]g"[-u]m or l[-e]*g[=u]m"), n. [F.
   l['e]gume, L. legumen, fr. legere to gather. So called
   because they may be gathered without cutting. See {Legend}.]
   1. (Bot.) A pod dehiscent into two pieces or valves, and
      having the seed attached at one suture, as that of the
      pea.

   Note: In the latter circumstance, it differs from a siliqua,
         in which the seeds are attached to both sutures. In
         popular use, a legume is called a pod, or cod; as, pea
         pod, or peas cod.

   2. pl. The fruit of leguminous plants, as peas, beans,
      lupines; pulse.

Source : WordNet®

legume
     n 1: an erect or climbing bean or pea plant of the family
          Leguminosae [syn: {leguminous plant}]
     2: the fruit or seed of any of various bean or pea plants
        consisting of a two-valved case that splits along both
        sides when ripe and having the seeds attached to one edge
        of the valves
     3: the seedpod of a leguminous plant (such as peas or beans or
        lentils)