| A.D. |
A.D. is an abbreviation of the Latin words "anno domini." The abbreviation A.D. is used in dates when people are talking about things in history that happened after Jesus Christ was born. The year that Jesus Christ was born is called "1 A.D." The year after that is called "2 A.D." Jesus Christ is considered both God and man in the religion of Christianity, and he is an important figure in the history of the world. The calendar that most people use nowadays was created by Christians. That's why the year of Christ's birth was chosen as a way to divide older times from newer times. This calendar is not the first or only calendar that people in the world have created, but most people nowadays use this particular calendar. Instead of "A.D.," though, people often use "C.E." nowadays, which stands for "Common Era" or "Christian Era." |
| ad |
"Ad" is a short word for "advertisement." An advertisement is something that tells people about things to buy or things that are happening. You often see advertisements on television. Sometimes you hear ads on the radio or see them online. Also, when you are outside, you sometimes see advertisements on signs. |
| adage |
an old familiar saying that shows the wisdom of a group of people; proverb. |
| adapt |
When a person adapts to a new situation, they make changes in the way they think or the way they do things. They adapt so that they can live or be happier under new conditions. If a plant or animal adapts, it changes its body or behavior so that it can live under new conditions, such as having to live in a new place or in a different climate. [2 definitions] |
| adaptable |
If a living thing is adaptable, it has the ability to change itself in order to survive or fit in better in a new situation. [2 definitions] |
| adaptation |
Adaptation is the process of adapting. When living things adapt, they change over a long period of time so that they can survive in new conditions and continue to multiply. [3 definitions] |
| add |
When you add something to another thing, you put it together with that thing, and you make it bigger or better. [4 definitions] |
| added |
further; extra. |
| addend |
a number or amount added to another to form a sum. |
| adder2 |
a small, venomous snake found in Europe and Asia. |
| addict |
a person who depends on something, such as a drug, that is usually harmful and cannot be easily given up. [3 definitions] |
| addiction |
If a person has an addiction, their body sends out signals that they must continue to take or take more of a certain a drug or similar substance. These signals cause a desire for the drug that is very, very strong, and it can make people do things that they would not normally do just to get it. Addiction is something that can ruin people's lives. Some drugs cause addiction, but most drugs that people take as medicine do not. |
| addition |
Addition is the act of putting something together with something else, usually to make it better or larger. [3 definitions] |
| additional |
If you have an additional thing, you have one more thing than what you had before. If you had two chairs before and somebody gives you an additional chair, it means you have three chairs now. Let's say your dad got only one small pizza for your birthday party but twenty kids came. You would probably need a lot of additional pizza! |
| additive |
a substance added to another substance in small amounts to change or improve it. |
| address |
Your address is the place where you live or where your mail is sent. [6 definitions] |
| add up |
to bring one to a logical conclusion; to make sense. |
| add up to |
reach (a certain total). |
| adenoid |
(usually plural) a mass of tissue that grows behind the nose in the upper part of the throat. When swollen, the adenoids can make breathing difficult. |
| adept |
having great skill or ability. |
| adequate |
If something is adequate, it is enough. If there is adequate food in the refrigerator, there is enough food. Nobody has to buy more food. If crops get adequate rain, they get enough rain. They don't need more rain than they get. [2 definitions] |