The Collaborative International Dictionary of English v.0.48:

Quandong \Quan"dong\, n. (Bot.)
   The edible drupaceous fruit of an Australian tree (Fusanus
   acuminatus) of the Sandalwood family; -- called also
   quandang.
   [1913 Webster]

WordNet (r) 3.0 (2006):

quandong
    n 1: Australian tree with edible flesh and edible nutlike seed
         [syn: quandong, quandang, quandong tree, Eucarya
         acuminata, Fusanus acuminatus]
    2: the fruit of the Brisbane quandong tree [syn: quandong,
       blue fig]
    3: Australian tree having hard white timber and glossy green
       leaves with white flowers followed by one-seeded glossy blue
       fruit [syn: quandong, quandong tree, Brisbane quandong,
       silver quandong tree, blue fig, Elaeocarpus grandis]
    4: red Australian fruit; used for dessert or in jam [syn:
       quandong, quandang, quantong, native peach]