agonic
/əˈɡɑnɪk/
adjective
- Relating to or denoting a line on a map where the magnetic declination is zero (the magnetic north and true north align).
- Scientists study the movement of the agonic line to understand geomagnetic changes.
- The agonic line shifts slightly each year due to changes in the Earth's magnetic field.
- Hikers use maps that show the agonic line to adjust their compass readings.