the.com/lithosphere

means The rigid outer shell of the Earth, made up of the crust and the topmost, solid part of the mantle, broken into the plates that drift and collide over geologic time.

from Built from Greek lithos, 'stone,' plus sphaira, 'sphere' — the same stone-root that gives us 'lithograph' and 'monolith.' The term was coined in the late 19th/early 20th century by geologists sorting Earth's interior into labeled shells (atmosphere, hydrosphere, lithosphere), naming each layer for the Greek element that defines it: here, simply, rock.