(of a source of light) to shine with a flickering light; to glimmer
We could see the lights of the village twinkling in the distance.
(chiefly of eyes) to be bright with delight
His shrewd little eyes twinkled roguishly.
To bat, blink or wink the eyes
To flit to and fro
A shining with fast intermittent light.
A very short period, notionally the time it takes to blink the eyes.
The housework was done in a twinkling.