nostril

Your nostrils are the two openings in your nose that let air in and out when you breathe. They also help you smell and help filter dust and other tiny bits from the air before it moves deeper into your body. They may flare when you are angry, upset, or breathing hard, and they often feel blocked when you have a cold. People and animals use them all the time without thinking about it. Sometimes a person may also have a piercing on one side of the nose.

The word "nostril" refers to each of the two openings in your nose. Air moves through them when you breathe, and smells enter through them too. They also help trap dust, pollen, and other tiny particles before those things travel farther into the body.

Think about a dog sniffing the ground. It learns a great deal through smell, using these small openings again and again. People depend on them too, even if we rarely notice it. The smell of fresh bread, flowers, or smoke reaches us through them.

In stories and everyday speech, the movement of the nostrils can also show feeling. A flared nostril may suggest anger, strong effort, or heavy breathing. When someone has a cold, these openings can feel blocked, which makes breathing and smelling harder. Although most people do not think about them very often, they are an important part of daily life.