Anything that blinks, such as the turn signal of an automobile.
Eye shields attached to a hood for horses, to prevent them from seeing backwards and partially sideways.
Whatever obstructs sight or discernment.
The eyelid.
A black eye.
In Conway's Game of Life, an arrangement of three cells in a row that switches between horizontal and vertical orientations in each generation.
To put blinkers on.
The farmer stopped to blinker his horse before riding into an area of heavy traffic.