Blinking

rapid closing and opening of the eyelid

Blinking is something that the body does. It is a fast closing and then reopening of the eyelids. It is semi-autonomic, meaning the person doesn't have to think about blinking to do it. People blink to keep the eyes wet by spreading water from the tear ducts around the eyes.[1] Blinking can also be used to spread feeling, in body language.

A human eye blinking in slow-motion.

References

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  1. "Blinking".