The inclination of a fold axis or other linear feature, measured in the vertical plane.

The inclination, with respect to the horizontal plane, of any linear structural element of a rock. The plunge of a fold is the inclination of the axis of the fold.

Plunge is the vertical angle in degrees from horizontal to a drill hole, ellipsoid axis, or variogram axis. This is often referred to as the dip angle of the drill hole or line segment. Downward dipping line segments have positive plunge. Horizontal segments have 0.0 degree plunge whereas vertical segments have +90.0 degree plunge.

The vertical angle a linear geological feature makes with the horizontal plane.

The attitude of a line in a plane which is used to define the orientation of fold hinges, mineralised zones and other structures.