n.1. Mathematics A surface containing all the straight lines that connect any two points on it.
2. A flat or level surface.
3. A level of development, existence, or achievement: scholarship on a high plane.
4. An airplane or hydroplane.
5. A supporting surface of an airplane; an airfoil or wing.
Word History: The plane in which we fly is properly named for a very important element of its structure

the wing that keeps it in the air. But the story behind this name is slightly complicated. To begin with,
plane in the sense of "winged vehicle," first recorded in April 1908, is a shortened form of
aeroplane. In June of that year
plane appeared in a quotation from the London
Times that mentioned one of the Wright brothers.
Aeroplane, first recorded in 1866, is made up of the prefix
aero-, "air, aviation," and the word
plane, referring to the structure designed to keep an air vehicle aloft. Originally the plane in such contexts was imagined as flat, hence the choice of the word
plane; in practice this surface must curve slightly in order to work. The word
aeroplane for the vehicle is first found in 1873. The first recorded appearance of the form
airplane in our current sense, which uses
air- instead of
aero-, is found in 1907. An American flies in an
airplane while a Briton still travels in an
aeroplane, but both can catch a
plane.