Definitions
1.nounA level or flat surface.
2.nounA flat surface extending infinitely in all directions (e.g. horizontal or vertical plane).
3.nounA level of existence or development. (eg, astral plane)
4.nounA 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.
5.noun(Unicode) Any of a number of designated ranges of sequential code points.
6.nounAn imaginary plane which divides the body into two portions.
7.adjectiveOf a surface: flat or level.