Planarity refers to the characteristic of being flat or two-dimensional. Some synonyms for planarity include flatness, levelness, evenness, uniformity, and smoothness. Another related term is "geometric plane," which refers to a flat surface that extends infinitely in all directions. The concept of planarity is commonly used in geometry and engineering, where it is important for objects or surfaces to be flat in order to function properly. Whether it is in designing buildings or creating 2D graphics, understanding the principles of planarity can greatly contribute to the success of a project.