Plain English Meaning

The line the Earth spins around. The two ends of that line are the true North Pole and the true South Pole — not the magnetic ones.

Full Definition

The imaginary straight line running through the Earth from the geographic North Pole to the geographic South Pole, around which the Earth rotates. True north and true south are defined by the points where this axis meets the Earth's surface.

Context Anchor

Seen in magnetic compass error discussions, especially when explaining variation: the angle between true north and magnetic north.

Derivation

Geographic' comes from the Greek geo (earth) and graphein (to describe or map). 'Axis' is Latin for a fixed line about which something turns. So a geographic axis is the line about which the Earth itself turns — the reference used by maps and .