In this reading 囱 is bound to 烟囱 (烟囱, 'chimney'), the everyday word for a smoke flue or factory stack.
Components
ideograph
囱cōng
chimney; smoke vent
囱 is a single self-contained graph: an outer frame with a crossing inner mark, picturing a vent or flue with smoke escaping through it. The pieces do not function as independent components, so it is treated as one unit.
Filed under radical 囗 (wéi, #31) by convention. 囗 is not a separate component in 囱, so no strokes are highlighted.
