An imaginary line round the earth passing through both the north pole and the north magnetic pole, at any point on which a compass needle points to true north.
More example sentences
- Navigators on these so-called agonic lines do not need to make the usual correction to their compasses.
- Extended lines that mark the constant magnetic declination away from the agonic line are called isogonic lines.
- When using a compass east of the agonic line, the needle points in a direction that is west of true north.
mid 19th century: from Greek agōnios, agōnos (from a- 'without' + gonia 'angle') + -ic.
Definition of agonic line in:
- The US English dictionary