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

jackhammer \jackhammer\ n.
   a hammer having a strong steel cutting blade, driven by
   compressed air in multiple rapid strokes, and used for
   cutting through pavement, concrete, or other hard substances.

   syn: air hammer, pneumatic hammer.
        wordnet 1.5

[2] : WordNet (r) 2.0

jackhammer
     n : a hammer driven by compressed air syn: air hammer, pneumatic
         hammer
see also:
air hammer pneumatic hammer 

Jackhammer >> J Words
Jackhammer, definition of term: Jackhammer
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