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

hackmatack \hack"matack`\ ha^k"m.ata^k`, n. of
   american indian origin. bot.
   the american larch larix americana, a coniferous tree
   with slender deciduous leaves; also, its heavy, close-grained
   timber. called also tamarack.
   1913 webster
see also:
larix americana tamarack 

[2] : WordNet (r) 2.0

hackmatack
     n : poplar of northeastern north america with broad heart-shaped
         leaves syn: balsam poplar, tacamahac, populus
         balsamifera
see also:
balsam poplar tacamahac populus balsamifera 

Hackmatack >> H Words
Hackmatack, definition of term: Hackmatack
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