[1] : The Collaborative International Dictionary of English v.0.48

hackberry \hack"ber`ry\ ha^k"be^r`ry^, n. bot.
   a genus of trees celtis related to the elm, but bearing
   drupes with scanty, but often edible, pulp. celtis
   occidentalis is common in the eastern united states. --gray.
   1913 webster
see also:
celtis celtis occidentalis 

[2] : WordNet (r) 2.0

celtis occidentalis
     n : large deciduous shade tree of southern united states with
         small deep purple berries syn: american hackberry
see also:
american hackberry 

Celtis >> C Words
Celtis, definition of term: Celtis
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