The flap that keeps food out of the trachea when swallowing is called the

The answer to your question is,

Epiglottis. The epiglottis is located behind the tongue and in front of the larynx.

-Mabel <3

the epiglottis moves back and forth to prevent the passage of food and liquids into the lungs ... When you swallow, the epiglottis flattens backward to cover the entrance to your larynx and prevent food from entering the lungs and windpipe. The epiglottis returns to its usual position after swallowing