“What does it mean when your left eye twitches?”

It may be a benign condition. If it persists, please see a neurologist.

Hi, this is most commonly due to benign fasciculation (https://en.wikipedia.org/wiki/Fasciculation) - essentially some motor neurons get sick or die (which happens all the time in healthy people too) and others next to them take over their innervation area, the muscles become over-sensitive and produce this phenomena, which can also be driven by aberrant signal through the motor nerves. If that persists for more than a few weeks, continues to expand, present in multiple different body parts or is associated with other symptoms such as weakness (in the affected area or elsewhere), medical attention should be sought. If the twitches are becoming spasms of the muscles around the eye and even larger parts of the face, it can also be a sign of so-called "hemifacial spasm".