What is the term for the difference between true north and magnetic north?

The correct term for the difference between true north and magnetic north is magnetic declination. This is an important concept in navigation and geography, as it helps navigators and map users understand how to convert magnetic compass readings into true bearings.

Magnetic declination varies depending on where you are on Earth and changes over time as the magnetic field shifts. By knowing the magnetic declination for a specific location, sailors, pilots, and hikers can accurately adjust their compass readings to ensure they are heading in the correct direction.

The other terms listed don't accurately represent this phenomenon. Declination angle is often used in contexts related to geometry or solar positioning but is not commonly used to describe the difference between true north and magnetic north. True bearing generally refers to the actual direction in degrees from true north to a point, and orientation offset typically refers to the angle between a reference direction and the desired direction, which doesn't specifically pertain to the difference between true north and magnetic north.