noun. 1  a. An old French dance resembling the gavotte, usually in 3/4 or 2/2 time beginning with an upbeat. 2  A movement in ballet in which the dancer transfers body weight quickly from foot to foot, usually on the balls of the feet, in a series of small steps.
Nystagmus is a condition where the eyes make repetitive movements. The eyes can jerk exclusively in one direction, or make back and forth movements. With nystagmus, the eye can look jittery and can affect both eyes or just one eye.
1 Complete Heterochromia â When both of the eyes are completely different colors (such as one eye brown and one eye blue). This is the most widely-known version of this vision condition.  Sectoral heterochromia â When there are two different colors in the same iris.