ydimension

ydimension is a term used to denote the second coordinate axis in a Cartesian coordinate system, typically representing vertical position in two-dimensional space. It is the dimension paired with the x-dimension and is fundamental to describing points, lines, and shapes in the plane. The concept appears across mathematics, physics, computer graphics, and geographic information systems.

In two-dimensional space, a point is written as (x, y), where x indicates horizontal displacement and y indicates vertical displacement relative to the x-axis. In many mathematical contexts, the y-dimension increases as you move upward. In computer graphics and some user interfaces, however, screen coordinates use (x, y) with y increasing downward, which changes the practical interpretation of movement along the y-dimension.

In three-dimensional space, the y-dimension is one of the three axes alongside x and z. It commonly represents vertical position in standard mathematical conventions, though some applications and coordinate systems designate y for depth or forward direction. The choice of orientation depends on the adopted convention (right-handed vs. left-handed systems) and the specific domain.

In data representations, the y-dimension is the second coordinate in a triplet or the second column in a matrix of coordinates. It is used to describe the vertical component of points, features in datasets, or projections onto the second axis when analyzing geometry or performing transformations.

See also: x-dimension, z-dimension, coordinate systems, axis terminology.