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steinkern

American  
[shtahyn-kern, -kurn, stahyn-] / ˈʃtaɪnˌkɛrn, -ˌkɜrn, ˈstaɪn- /

noun

Archaeology.
  1. the fossilized outline of a hollow organic structure, as a skull or a mollusk shell, formed when mud or sediment consolidated within the structure and the structure itself disintegrated or dissolved.


Etymology

Origin of steinkern

< German Steinkern literally, stone, pit (of a fruit), equivalent to Stein stone + Kern core, kernel