Sentence:  Hoag pushed open the door : at the far end of the long dark room Muller was faintly silhouetted against the window , the rifle still raised ; he stood with his feet apart on a kitchen table he had dragged to the <WSD>sill</WSD> . 
Meaning of the word marked with <WSD> tags:  structural member consisting of a continuous horizontal timber forming the lowest member of a framework or supporting structure