/pleɪn/
noun
A level or flat surface.A flat surface extending infinitely in all directions (e.g. horizontal or vertical plane).A level of existence or development. (eg, astral plane)A roughly flat, thin, often moveable structure used to create lateral force by the flow of air or water over its surface, found on aircraft, submarines, etc.(Unicode) Any of a number of designated ranges of sequential code points.An imaginary plane which divides the body into two portions.adjective
Of a surface: flat or level.