Other forms: geodes
A geode is a dull stone that is hollow and crystal-lined inside. Crack open a geode, a hollow geode, a geode of amethyst.
From outside it is an unremarkable lump, which is the whole appeal, and nobody knows what is in one until it is cut. They form when a cavity in rock fills slowly with mineral-rich water and crystals grow inwards.
1noungeodeA dull stone that is hollow and crystal-lined inside.
“When we cracked the round grey geode open, it was full of purple crystals.”
geode is a stone.
Greek geodes means earthlike, from ge, earth.
Ancient Greek
γεώδης — earthlike
Latin
geōdēs
French
géode
English, today
geode
Built from
From French géode, from Latin geōdēs, from Ancient Greek γεώδης (“earthlike”), equivalent to γῆ (“earth”) + -ώδης.
Etymology from Wiktionary, CC BY-SA