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

backpack \back"pack\ n.
   a bag carried on the back, supported by straps looped over
   the shoulders.

   syn: knapsack; rucksack; haversack. wordnet 1.5

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

backpack \back"pack\ v. i.
   to hike while carrying a backpack; -- often used in the form
   go backpacking; as, to backpack through the forest.
   pjc
see also:
go backpacking 

[3] : WordNet (r) 2.0

backpack
     n : a bag carried by a strap on your back or shoulder syn: back
         pack, knapsack, packsack, rucksack, haversack
     v : hike with a backpack; "every summer they are backpacking in
         the rockies" syn: pack
see also:
back pack knapsack packsack rucksack haversack pack 

Back-Pack >> B Words
Back-Pack, definition of term: Back-Pack
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