| uncle |
Your uncle is the brother of your father or mother. Also, if a sister of your father or mother marries someone, that person is your uncle. |
| uncomfortable |
If a chair makes you uncomfortable, it makes your body feel a little bad. Maybe the chair is too hard or it has a funny shape. It makes you want to sit in a different chair. If your clothes are too tight, you are probably uncomfortable too. Sometimes a thing that someone says or does can make you feel uncomfortable in a different way. It can make you feel just a little scared, strange, or embarrassed. |
| uncover |
When you uncover a thing, you take away something that is over the top of it. [2 definitions] |
| under |
If a boat is going down a river and comes to a bridge, the boat will go under the bridge. When it is raining outside, people often walk under an umbrella. When something is under another thing, it is below it. [4 definitions] |
| understand |
When you understand something, you know what it means. |
| underwear |
Underwear is the clothing you wear next to your skin under other clothing. |
| unhappy |
When someone is unhappy, they are sad or upset. |
| unicorn |
A unicorn is a make-believe animal. A unicorn has the body of a horse and one long horn on its forehead. |
| uniform |
A uniform is a special set of clothing that everybody in a certain group must wear. In some schools, all the children wear a uniform. The uniform is a little different for girls than for boys. Police officers, mail carriers, airplane pilots, and fire fighters are some other people who wear uniforms. [2 definitions] |
| unit |
A unit is a particular amount that is used to measure things. The inch and the foot are units for measuring how long something is. The pound and the ounce are units for measuring how much something weighs. |
| unite |
When things or people unite, they join together. |
| United Arab Emirates |
The United Arab Emirates is a country on the continent of Asia. It is in an area of the world called the Middle East, and it lies on the shore of a body of water called the Persian Gulf. The United Arab Emirates is a country with desert and mountains. It has oil and gas under the ground that it sells to other countries. These products are used for fuel around the world. Fishing and growing fruits called dates are also important ways to make a living in the United Arab Emirates. |
| United Kingdom |
The United Kingdom is a country in Europe. It is made up of England, Scotland, Wales, and Northern Ireland. Most of the United Kingdom is on an island called Great Britain, but Northern Ireland is on an island called Ireland. These two islands are between the Atlantic Ocean and a sea called the North Sea. They are not very far from the countries of France and the Netherlands. |
| United States of America |
The United States of America is a country that is mostly on the continent of North America. A short name for this country is the United States. The United States has many different climates and types of land. There are forests, plains, farm lands, mountains, deserts, swamps, and tropical regions. There are large cities and many small towns. People of the United States of America are called Americans. |
| universe |
The universe is everything that exists, including the earth, planets, and stars. |
| university |
A university is a large school where students can go after high school. |
| unless |
When you say you are going swimming today unless it rains, it means that rain is the only reason you might not go swimming. |
| untie |
When you tie a knot, you make a knot in something. When you untie a knot, you make it loose until there is no more knot. |
| until |
If you play until dinner is ready, you play before dinner and then stop playing when dinner is ready. [3 definitions] |
| unusual |
When something is unusual, it does not happen very often, or we don't see it often. |
| up |
When you go up, you move to a higher place. When an airplane goes up, it goes from the ground into the sky, or it goes from one place in the sky to a higher place. [8 definitions] |