The geosphere is the scientific name for the solid parts of a planet. When you go for a hike, you can think of the ground beneath your feet as part of the Earth's geosphere.
In Earth science or geoscience, the geosphere refers to the parts of our planet that are solid (like the mantle and crust). The liquid and gaseous parts are called the hydrosphere and atmosphere. Geosphere, coined in the late 19th century, was modeled after atmosphere, with the Greek prefix geo-, "earth."