| afloat |
on the water; floating. |
| algae |
organisms that live mainly in the water and make their food through photosynthesis. Algae are different from plants in that they have no true leaves, roots, or stems. Seaweeds are algae. "Algae" is a plural noun; the singular form is "alga." |
| alligator |
a large reptile with short legs, a long body and tail, and a long, wide snout. Alligators are protected by thick skin with many hard bumps. They live in rivers, lakes, swamps, and other bodies of water in the southeast United States and in China. They usually eat insects, fish, turtles, snakes, birds, and other water animals, but have been known to attack small land mammals. They are closely related to crocodiles. Chinese alligators are endangered because their habitat is being changed by people. |
| ammonia |
the liquid made from mixing ammonia gas with water. Certain cleaners are made with ammonia. [1/2 definitions] |
| amoeba |
a tiny living thing made of only one cell. Amoebas move by changing their shape. They eat by wrapping their bodies around their food. Amoebas live in fresh and salt water, soil, and in animals. Most kinds of amoebas can only be seen through a microscope. |
| amphibian |
a small animal that spends part of its life cycle in water and part of its life cycle on land. Amphibians hatch in water and breathe with gills. Then they develop lungs so the adults can breathe air. Amphibians are cold-blooded animals with skeletons inside their bodies. Frogs, toads, and salamanders are amphibians. [2 definitions] |
| amphibious |
able to live both on land and in water. [2 definitions] |
| antifreeze |
a substance that lowers the freezing point of a liquid such as water. |
| aquaculture |
the farming of plants and animals that live in water. |
| aquarium |
a tank or other container filled with water in which water animals and plants are kept. [2 definitions] |
| Aquarius |
a constellation located between Capricorn and Pisces. Aquarius is also called the Water Bearer. [2/3 definitions] |
| aquatic |
of or taking place on the water. [2 definitions] |
| aqueduct |
a channel or pipe built to carry water over a long distance. [1/2 definitions] |
| aquifer |
a layer of rock, sand, or gravel that contains water from which wells and springs are supplied. |
| Aral Sea |
formerly, a very large, single lake in Central Asia. Once one of the world's largest lakes, the Aral Sea has lost a great deal of its water in recent times and it has divided into separate parts. The southeastern part of the Aral Sea has become entirely dry and is called a desert now. |
| arroyo |
a steep ditch carved in a plain or desert by the force of running water. Arroyos are usually dry except after a heavy rainfall. |
| bagel |
a kind of bread roll that is shaped like a ring. Bagel dough is boiled in water before it is baked. |
| bail3 |
to remove water from a boat by scooping. |
| baleen |
the bony, flexible strips in the upper jaws of whales that feed by filtering food from ocean water. These whales use baleen to strain large amounts of small food such as shrimp from the water. |
| baptism |
a Christian ceremony in which someone who wishes to join the church is sprinkled with water or dipped in water. |
| baptize |
to perform the Christian ceremony of dipping in or sprinkling with water as a symbol of becoming a member of the church. [1/2 definitions] |