kettle lid radical (no. 8)
亠 is a non-standalone radical shape representing a kettle lid or a top cover. It is used as a component in other characters rather than as an independent word.
亠 is a stylized pictograph of a lid or cover, used as a radical in characters related to covering or top structures.
Picture a simple flat lid with a small knob on top: 亠 is the kettle lid radical.
For トウ, imagine a toe touching the hot kettle lid: toe -> トウ, and the lid covers the pot.
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