1. 
[syn: convulsive, spasmodic, spastic]
2.  resembling a convulsion in being sudden and violent; 
- Example: "a convulsive rage"
- Example: "convulsive laughter"
The Collaborative International Dictionary of English v.0.48:
Convulsive \Con*vul"sive\, a. [Cf. F. convulsif.]
   Producing, or attended with, convulsions or spasms;
   characterized by convulsions; convulsionary.
   [1913 Webster]
         An irregular, convulsive movement may be necessary to
         throw off an irregular, convulsive disease. --Burke.
   [1913 Webster]
WordNet (r) 3.0 (2006):
convulsive
    adj 1: affected by involuntary jerky muscular contractions;
           resembling a spasm; "convulsive motions"; "his body made
           a spasmodic jerk"; "spastic movements" [syn:
           convulsive, spasmodic, spastic]
    2: resembling a convulsion in being sudden and violent; "a
       convulsive rage"; "convulsive laughter"