'jackhammer' definitions:

Definition of 'jackhammer'

From: WordNet
noun
A hammer driven by compressed air [syn: air hammer, jackhammer, pneumatic hammer]

Definition of 'jackhammer'

From: GCIDE
  • 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]