Prefix Hydro-

3. The scientific study of life in water environments. Hydrobiologists research plants, animals, and microorganisms that live in oceans, rivers, lakes, and other aquatic habitats.
6. Relating to electricity produced by the power of moving water. Hydroelectric dams use flowing rivers to turn generators and create clean energy.
8. A chart or graph that shows how the flow of water in a river or stream changes over time. Hydrographs help scientists track flooding, droughts, and seasonal water patterns.
9. To add water to something, or to drink enough water to keep your body healthy. When you hydrate, you're giving your body the water it needs to function properly.

1. A colorless, odorless gas that is the lightest and most abundant element in the universe. Hydrogen can be used as a clean fuel source and is found in water (H₂O).
2. Energy created by using the force of moving or falling water. Hydropower is a renewable energy source that can generate electricity without producing pollution.
4. A boat with special underwater wings that lift it above the water's surface when moving fast. This design reduces drag and allows the boat to travel more quickly and smoothly.
5. The study of sound in water environments. Scientists use hydroacoustics to study marine animals, map the ocean floor, and detect underwater objects using sound waves.
7. A water outlet, usually found on streets, that firefighters connect hoses to for fighting fires. Fire hydrants provide a strong flow of water from underground pipes.