Which term describes the water portion of Earth?

The term that describes the water portion of Earth is "Hydrosphere." This concept encompasses all forms of water found on the planet, including oceans, rivers, lakes, glaciers, and even groundwater. The hydrosphere plays a critical role in the Earth's systems, influencing weather, climate, and living organisms. It interacts dynamically with the atmosphere (the layer of gases surrounding the Earth), the lithosphere (the solid outer part of the Earth), and the geosphere (which refers to the Earth's interior and landforms). Understanding the hydrosphere is vital for studying water cycles, ecosystems, and environmental sciences.