An outburst of madness

From the New York Times' story last night about the massacre at an immigration services center in Binghamton, N.Y.:

A gunman invaded an immigration services center in downtown Binghamton, N.Y., during citizenship classes on Friday and shot 13 people to death and critically wounded 4 others before killing himself in a paroxysm of violence that turned a quiet civic setting into scenes of carnage and chaos.

Using the Times' handy double-click on a word to get a definition from the American Heritage Dictionary feature, I found that a paroxysm is:

  • 1. A sudden outburst of emotion or action: a paroxysm of laughter.
  • 2a.  A sudden attack, recurrence, or intensification of a disease.
  • 2b. A spasm or fit; a convulsion.

And the etymology: Middle English paroxism, "periodic attack of a disease"; from Medieval Latin paroxysmus; from Greek paroxusmos; from paroxūnein, "to stimulate, irritate."