Answer: saccade

AnswerCrossword Clue
SACCADEQuick rein pull
SACCADEQuick pull on reins.
SACCADEA violent check of the reins.
saccadea rapid jerky movement of the eye
saccadethe movement of the eye when it makes a sudden change, as in reading.
saccadethe series of small, jerky movements of the eyes when changing focus from one point to another
saccadethe act of checking a horse quickly with a single strong pull of the reins