WordNet (r) 3.0 (2006):

motion sickness
    n 1: the state of being dizzy or nauseated because of the
         motions that occur while traveling in or on a moving
         vehicle [syn: motion sickness, kinetosis]

Moby Thesaurus II by Grady Ward, 1.0:

33 Moby Thesaurus words for "motion sickness":
   Minamata disease, airsickness, altitude sickness, anoxemia, anoxia,
   anoxic anoxia, anthrax, black lung, caisson disease, car sickness,
   chilblain, decompression sickness, frostbite, immersion foot, itai,
   jet lag, lead poisoning, mal de mer, mercury poisoning, nausea,
   pneumoconiosis, qualm, qualmishness, queasiness,
   radiation sickness, radionecrosis, red-out, seasickness,
   squeamishness, sunstroke, the bends, trench foot, vomiting