MOTION SICKNESS
Motion sickness or kinetosis is a condition in which a disagreement exists between visually perceived movement and the vestibular system's sense of movement. Depending on the cause it can also be referred to as seasickness, carsickness, simulation sickness, airsickness, or space sickness.Dizziness, fatigue, and nausea are the most common symptoms of motion sickness.Sopite syndrome is also a side effect of motion sickness. In fact, nausea in Greek means seasickness (naus means ship). If the motion causing nausea is not resolved, the sufferer will frequently vomit. Unlike ordinary sickness, vomiting in motion sickness tends not to relieve the nausea.About 33% of people are susceptible to motion sickness even in mild circumstances such as being on a boat in calm water, although nearly 66% of people are susceptible in more severe conditions.Approximately 50% of the astronauts in the U.S. space program have suffered from space sickness.Individuals and animals without a functional vestibular system are immune to motion sickness.(1)

Source (1) Wkipedia