The point, in any trajectory of an object in space, where it is farthest from the Earth.
The highest point.
The point, in an orbit about the Earth, that is farthest from the Earth: the apoapsis of an Earth orbiter.
The point, in an orbit about any planet, that is farthest from the planet: the apoapsis of any satellite.
the vertical distance below a surface; the degree to which something is deep
the deepest part (usually of a body of water)
the intensity, complexity, strength, seriousness or importance of an emotion, situation, etc.
a very remote part.
the total palette of available colors
a pair of toothed wheels which work together
lowness
the property of appearing three-dimensional
the number of simple elements which an abstract conception or notion includes; the comprehension or content
the distance between the front and the back, as the depth of a drawer or closet
the most severe part
the perpendicular distance from the chord to the farthest point of an arched surface
the lower of the two ranks of a value in an ordered set of values