| asphalt |
a sticky black substance like tar. Asphalt is found naturally or obtained when oil is refined. It is used for making roads and roofs and for making things waterproof. [1/2 definitions] |
| bioluminescence |
light given off naturally by certain kinds of insects, fish, or bacteria. The bioluminescence of fireflies allows them to blink on and off in the dark. |
| biome |
A biome is a type of region on the earth where certain types of plants and animals live naturally because they have adapted to the soil, climate, and other conditions that exist there. Forest and desert are two types of biome. |
| cobblestone |
a naturally rounded stone about the size of a fist, at one time used to pave streets. |
| concentrate |
A concentrate is something in concentrated form, such as a fruit juice concentrate. When people concentrate juice, much of the water that is naturally in the juice is taken away. [1/4 definitions] |
| fauna |
When we talk about fauna, we are talking about animals in a general way, or all the animals that live naturally in a particular place. The word "fauna" contrasts with the word "flora," which is talking about plants only. |
| fluent |
able to speak or write easily and naturally. |
| forgive |
If someone does something bad and you forgive them, you decide in your mind that you are not angry anymore, or your bad feelings just go away naturally. You excuse them for what they did. [1/2 definitions] |
| greenhouse effect |
the warming of the earth's surface and lower atmosphere that is caused by reflected sunlight being trapped by certain gasses that are emitted on earth. Light from the sun travels through space and enters earth's atmosphere, naturally warming the planet and making it possible for humans to live on it. Once sunlight hits the earth, though, it bounces back into space. If it did not go back into space, the earth would be too hot to live on. Gases such as carbon dioxide and methane that are sent into the air from earth are capable of trapping sunlight that should return to space. The warmth created by the trapped sunlight is called the greenhouse effect. The greenhouse effect can be seen on other planets in the universe if gases emitted from the planet trap light from a star. |
| immune |
protected from a disease, either naturally or by getting a vaccine. [1/2 definitions] |
| native |
an animal or plant found naturally in a given place. [2/6 definitions] |
| naturally |
When something happens naturally, it happens according to the ways of nature and not through a man-made process. [4 definitions] |
| of course |
naturally. [1/2 definitions] |
| organic |
produced or producing naturally, without using pesticides or other added chemicals. [1/2 definitions] |
| ozone |
a form of oxygen that occurs when oxygen is exposed to an electrical charge, like lightning. It is found naturally in Earth's atmosphere. |
| pack1 |
a group of animals that are alike and stay together naturally. [1/9 definitions] |
| salt water |
water with naturally occurring salt in it, such as the water in the sea. [1/2 definitions] |
| shrub |
Shrubs are bushes. A shrub is a plant that has a hard stem and thin, hard branches that begin very close to the ground. Some shrubs can get as high as a small tree. Shrubs grow naturally, but people like to use them for outdoor decoration too. They often plant shrubs around houses and other buildings, and they trim them and keep them fairly short. |
| species |
a group of living things that naturally produce young with other members of the same group but not with those of other groups. |
| spit1 |
(informal) "Spit" is another word for "saliva." Saliva is the clear liquid that forms naturally in your mouth. [1/3 definitions] |
| stone |
a piece of rock shaped naturally or cut for use in building or some other particular use. [1/6 definitions] |