- a hollow concretionary or nodular stone often lined with crystals.
- the hollow or cavity of this.
- any similar formation.
Origin of geode
Examples from the Web for geode
The geode is a spherical and apparently solid stone, but when broken is found to be hollow and coated with crystals.The Smoky God
Willis George Emerson
The geode has a hollow cell within, lined with beautiful crystals of many colors.First Across the Continent
No date; no place mentioned; we note the suggestion that it was only a geode, which had been upon the ground in the first place.The Book of the Damned
A geode is a hollow shell of stone, usually quartz, lined with crystals pointing toward the center.The Chautauquan, Vol. III, March 1883
The Chautauquan Literary and Scientific Circle
Geode, an irregular shaped stone, containing a small cavity.A Manual of the Antiquity of Man
J. P. MacLean
- a cavity, usually lined with crystals, within a rock mass or nodule
Word Origin and History for geode
rounded stone with a hollow center lined with crystals, 1670s, from French géode, from Latin geodes, from Greek geodes "earthy, earth-like," from ge "earth" (Homeric gaia; see Gaia) + -oides, adjective suffix, "characterized by." Perhaps so called in reference to the "earthy" minerals inside.
- A cystlike space with or without an epithelial lining, usually observed in subarticular bone in arthritic disorders.
- A small, hollow, usually rounded rock lined on the inside with inward-pointing crystals. Geodes form when mineral-rich water entering a cavity in a rock undergoes a sudden change in pressure or temperature, causing crystals to form from the solution and line the cavity's walls.