Geosphere (J-eoos-fere) are all of the regions of Earth and the atmosphere (other regions including lithosphere, hydrosphere, cryosphere, and atmosphere). You could look into Wikipedia's definition as "The geosphere may be taken as the collective name for the lithosphere, the hydrosphere, the cryosphere, and the atmosphere", or the standardized dictionary definition as a lithosphere (same thing at dictionary.com)... or maybe into earth.rice.edu's definition as "The geosphere is considered that portion of the Earth system that includes the Earth's interior, rocks and minerals, landforms and the processes that shape the Earth's surface" - or a simplified version of the definition: "The geosphere includes the rocks and minerals on Earth – from the molten rock and heavy metals in the deep interior of the planet to the sand on beaches and peaks of mountains. The geosphere also includes the abiotic (non-living) parts of soils, and the skeletons of animals that may become fossilized over geologic time.".
But.. hold up! We've got to define the words at the beginning first in italics! The lithosphere, according to a dictionary-definition, is "the crust and upper mantle of the earth"... while... when we go to a science-related website for a definition (NatGeo), we get "The lithosphere is the solid, outer part of the Earth. The lithosphere includes the brittle upper portion of the mantle and the crust, the outermost layers of Earth’s structure". Now, onwards to hydrosphere, we simply get "The hydrosphere is the world of water that surrounds all of us.", but remember! The frozen waters of the planet are the Cryospheres. And, obviously, the atmosphere is the surrounding gases around the Earth (textbook definition).
As you can see with the heaps of definitions and tidbits, the Geosphere is one confusing term. But, in modern text books, the Geosphere are the solid parts of the Earth. Though, it is used as the term, lithosphere, sometimes (as you can see with the dictionary-term definitions).
Make sure to review this article, as there is a lot of information to be memorized! And I hope for you an exciting journey through Earth science!