\PAIR-uhk-siz-uhm\, noun: 1 (Medicine) A sudden attack, intensification, or recurrence of a disease 2 Any sudden and violent emotion or action; an outburst; a fit
A paroxysm is a series of sudden, violent, uncontrollable movements that your body makes because you are coughing, laughing, or in great pain. He broke into a paroxysm of coughing. = spasm