The Collaborative International Dictionary of English v.0.48:

Dangleberry \Dan"gle*ber`ry\, n. (Bot.)
   A dark blue, edible berry with a white bloom, and its shrub
   (Gaylussacia frondosa) closely allied to the common
   huckleberry. The bush is also called blue tangle, and is
   found from New England to Kentucky, and southward.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Gaylussacia frondosa
    n 1: huckleberry of the eastern United States with pink flowers
         and sweet blue fruit [syn: dangleberry, dangle-berry,
         Gaylussacia frondosa]