The Collaborative International Dictionary of English v.0.48:

nagami \nagami\ n.
   A shrub (Fortunella margarita) bearing oval-fruited
   kumquats. See also kumquat.

   Syn: nagami kumquat, oval kumquat, Fortunella margarita.
        [WordNet 1.5 +PJC]

WordNet (r) 3.0 (2006):

Fortunella margarita
    n 1: shrub bearing oval-fruited kumquats [syn: nagami, nagami
         kumquat, oval kumquat, Fortunella margarita]