An Etymological Dictionary of Astronomy and Astrophysics

Solid → rock present beneath any → soil, → sediment, or other surface cover. In some locations it may be exposed at earth’s surface.

Etymology (EN): Bedrock, from bed (O.E. bed, from P.Gmc. *badjam “sleeping place dug in the ground;” PIE *bhedh- “to dig, pierce”) + → rock.

Etymology (PE): Sangbastar, from sang “stone, rock,”
→ stone, + bastar “bed” (Mid.Pers. vistarak, cognate with Mod.Pers. gostar “a bed; spreading; scatterer,” Av. star-, starəta- “spread,” from star- “to spread,” Skt. strnâti).