the GNU version of the Collaborative International Dictionary of English
A circular saw; -- so called from the buzzing it makes when running at full speed.
The Century Dictionary and Cyclopedia
n. A circular saw: so called from its sound when in action.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. a power saw that has a steel disk with cutting teeth on the periphery; rotates on a spindle
Word Usage
"The buzzsaw is a powerful system of censorship in this country that is revealed to those reporting on extremely sensitive stories, usually having to do with high level government or corporate malfeasance."