To close and open the eyes quickly. She blinked rapidly to clear the dust from her eyes.
To flash on and off in a regular or intermittent way. The warning light blinked on the dashboard.
To react with surprise or confusion. He blinked in disbelief at the unexpected news.
To ignore or pretend not to notice, especially something wrong or undesirable (often followed by "at"). Regulators cannot continue to blink at these obvious safety violations.