par·ox·ysm 
(părək-sĭz′əm)
(părək-sĭz′əm)n.
1. A sudden outburst of emotion or action: a paroxysm of laughter.
2.
a. A sudden attack, recurrence, or intensification of a disease.
b. A spasm or fit; a convulsion.
[Middle English paroxism, periodic attack of a disease, from Medieval Latin paroxysmus, from Greek paroxusmos, from paroxūnein, to stimulate, irritate : para-, intensive pref.; see PARA-1 + oxūnein, to goad, sharpen (from oxus, sharp; see ak- in the Appendix of Indo-European roots).]
par′ox·ysmal (-ək-sĭzməl) adj.
par′ox·ysmal·ly adv.