1 [no object] suffer violent involuntary contraction of the muscles, producing contortion of the body or limbs:she convulsed, collapsing to the floor with the pain
[with object] (of an emotion, laughter, or physical stimulus) cause (someone) to make sudden, violent, uncontrollable movements:she rocked backwards and forwards, convulsed with helpless mirth
2 [with object] throw (a country) into violent social or political upheaval:a wave of mass strikes convulsed the Ruhr, Berlin, and central Germany