Sentence:  The meat wagon , therefore , was not out in front of the house any more , but the cluster of squad cars was still there and there was a cop on the <WSD>door</WSD> downstairs to screen any comings and goings . 
Meaning of the word marked with <WSD> tags:  the entrance (the space in a wall) through which you enter or leave a room or building; the space that a door can close