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root (of a plant)
root (of a tooth, hair, etc.); center (of a pimple, etc.)
root (of all evil, etc.); source; origin; cause; basis
one's true nature
(fishing) reef
「根」 has another reading with different meanings.
大きな木の根が地面から見えている。
Tree roots are visible.
虫歯が進行して歯の根まで痛みが広がっている。
The cavity has progressed and pain has spread to the root of the tooth.
この木の根が深くて、抜くのが大変です。
This tree's roots are deep, so it's hard to pull out.