What does lithosphere mean?
The lithosphere is the rigid outer shell of Earth, including both the crust and the rigid uppermost portion of the mantle. It forms the hard, plate-like layer whose sections move over the weaker material beneath them. Because it combines crust and upper mantle, the term is broader than “the crust,” and it is also distinguished from the ductile asthenosphere. In ordinary conversation, “lithosphere” is mainly a technical geological term, while specialists may shorten it to “the lithosphere” when discussing plate motion, mineral composition, or the boundary between rigid and ductile Earth. The word is useful because it names a mechanically distinct layer rather than treating the planet's surface, crust, and mantle as a single uniform shell. Its geological meaning also supports careful comparisons with the atmospheres, hydrospheres, and biospheres that surround Earth's interior and surface.
nounThe rigid outer part of Earth, comprising the crust and the rigid uppermost portion of the mantle. It is divided into tectonic plates that move over the weaker mantle below.
- The rigid outer shell of a planet, especially Earth, consisting of the crust and the rigid uppermost part of the mantle.
"The lithosphere is broken into tectonic plates whose slow movement shapes the continents and ocean basins."
"Scientists use seismic data to estimate the thickness of the lithosphere beneath different regions."
"The lithosphere interacts with the atmosphere, hydrosphere, and biosphere at Earth's surface."
The plural is used when referring to the rigid outer layers of different planets or to separate geological bodies.
"The lithospheres of Earth and Mars have different thicknesses and compositions."
Your feet rest on the lithosphere—a rigid rocky shell made of moving plates above Earth's softer mantle.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does lithosphere come from?
The word is an English scientific compound formed from the Greek lithos, meaning “stone,” and sphaira, meaning “sphere.” It entered English geological usage in the late nineteenth century to denote Earth's rigid outer shell. Related English words such as “lithography,” “lithology,” and “lithic” preserve the same Greek stone-forming element.
Related word forms
How lithosphere is actually used
This is primarily a technical term in geology, geophysics, and planetary science. It is broader than “crust” and is not normally used figuratively.
Easily confused with lithosphere
The lithosphere is the rigid outer shell of Earth, whereas the asthenosphere is the weaker, ductile layer of the upper mantle beneath it.