晕动病或运动病，生活中通常被称为晕车、晕机和晕船，是一种平衡失调的疾病。当人眼所见到的运动与前庭系统感觉到的运动不相符时，就会有昏厥、恶心、食欲减退等症状出现。严重者会呕吐。 头晕，房屋物体与灯顺时钟旋转（天旋地转），流冷汗，无法站立，感觉要晕倒，意识清础，疲惫和恶心是晕动病的典型症状。表现为疲倦和劳累的昏睡综合症也被认为和晕动病有关。Nausea 在希腊语里意味着晕船（单词前缀naus是船的意思）。如果由于船体晃动导致的恶心感觉没有被缓解，患者就会频繁的呕吐。和一般的病症不同，晕动病导致的恶心并不会在呕吐后得到缓解。

Motion sickness, also known as kinetosis and travel sickness, 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, car sickness, simulation sickness or airsickness.