Definition of "nystagmus" []

• A rapid, involuntary, oscillatory motion of the eyeball. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "There ` s also a test called nystagmus, in which an officer either a pen or his finger and actually tests the nystagmus, which is a natural twitching of somebody ` s eyes in response to a finger that ` s being moved from left to right."
• "Her left shoulder, sometimes both shoulders, shook frequently, as did her eyes, a condition called nystagmus, making objects appear as if they were bouncing."
• "Because of my earlier research, I did not doubt for a second that the nystagmus was the result of a reflex action of the semi-circular canals."