Found 2 items, similar to agonic line.
English → English (WordNet) Definition: agonic line agonic line n : an imaginary line connecting points on the Earth's surface where the magnetic declination is zero
English → English (gcide) Definition: Agonic line Agonic \A*gon"ic\, a. [Gr. ? without angles; 'a priv. + ? an angle.] Not forming an angle. [1913 Webster] Agonic line (Physics), an imaginary line on the earth's surface passing through those places where the magnetic needle points to the true north; the line of no magnetic variation. There is one such line in the Western hemisphere, and another in the Eastern hemisphere. [1913 Webster]