tortoise-core

[ tawr-tuh s-kawr, -kohr ]
/ ˈtɔr təsˌkɔr, -ˌkoʊr /

noun

Archaeology. a late Lower and Middle Paleolithic stone core characteristic of the Levalloisian tradition of toolmaking, having a rounded top and flattish bottom and prepared in advance to permit the removal of a single ellipsoid flake with one blow from a stone hammer.

Origin of tortoise-core

First recorded in 1915–20