#windowsill  the sill of a window; the horizontal member at the bottom of the window frame
  supertype:  #sill  structural member consisting of a continuous horizontal timber forming the lowest member of a framework or supporting structure
  part of:  #window_frame  the framework that supports a window
     part of:  #window  a framework of wood or metal that contains a glass windowpane and is built into a wall or roof to admit light or air
        part of:  #edifice__building  a structure that has a roof and walls and stands more or less permanently in one place; "there was a three-story building on the corner"; "it was an imposing edifice"

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