what is depth in measurement

Depth is a measurement of distance, specifically the distance between a point and a chosen reference surface, measured downward and perpendicularly from the surface. It is commonly used to describe the third dimension of a three-dimensional object, along with width and height. In the context of measuring furniture, depth refers to the distance or length that an item comes out from the wall and into the room. In the context of measuring bodies of water, depth refers to the perpendicular vertical distance from the surface of the water to some point below the water. When measuring the dimensions of a three-dimensional figure, the terms length, height, width, and depth can be used interchangeably depending on the context and what seems wide or deep about the figure.