He knocked on the door.
													
																	Sliding door definitin. 
									
	
		
	
																	Sliding door definition is a door that opens and closes by sliding sideways instead of by swinging on hinges. 
																	Sliding doors can be mounted either on top of a track below or be suspended from a track above and some types disappear in a wall when slid open. 
																	A sliding door is a type of door which opens horizontally by sliding usually parallel to a wall. 
																	Door a swinging or sliding barrier that will close the entrance to a room or building or vehicle. 
															
													
									
	
		
	
																	Learner s definition of sliding door. 
																	A door that opens and closes by sliding sideways instead of by swinging on hinges. 
																	Sliding door a door that opens by sliding instead of swinging.