No standalone use in modern Chinese; a literary word for a roof ridge, seen in classical descriptions of grand buildings. The top 蒙-shaped stack carries the sound and the bottom is the tile radical 瓦.
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Literary only; appears in classical prose and poetry, not in everyday speech.
The upper stack — grass top over a netted middle and a cover — is the same shape that gives 蒙 and 梦 their sound, here read méng. Its "covering" flavor also suits a roof that caps a building.
