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stone (of a fruit); pit; pip
core (of an organization, team, etc.); nucleus; heart
nuclear weapons
nucleus (of an atom)
nucleus (of a cell)
condensation nucleus
(planetary) core
ring (in a cyclic compound)
kernel; core
nucleus (of a cultured pearl)
「核」 has another reading with different meanings.
桃の核を庭に植えてみた。
I tried planting a peach pit in the garden.
問題の核心に早く迫りましょう。
Let's get to the heart of the matter.
梅の核は固いので歯で噛まないように。
Plum pits are hard, so don't bite them.