A plane which declines from the zenith, or inclines toward the horizon.

(mechanics) One of the simple machines; a sloping surface such as a ramp such that an object can be raised with less effort than being lifted vertically.

(mathematics, astronomy) The mean plane occupied by the orbit of a satellite during a precession cycle; the plane normal to the orbital precession pole of the satellite.

An airplane that supposedly could detect oil fields underground.

In art, the imaginary plane correspondent with the physical surface of a drawing, painting or print.

(geometry) The set of all points in a planar coordinate system.

(parapsychology, Theosophy) A supernatural plane of existence, propounded by esoteric philosophies, some religious teachings, and New Age thought.

(mathematics) the locus of points in the Euclidean plane that satisfies some geometric or algebraic definition; a curve in a plane (as opposed to higher-dimensional space)

(mathematics) Two-dimensional Euclidean space.

(mathematics) a representation of the space of complex numbers