isogonic line
noun
Definition of isogonic line
: an imaginary line or a line on a map joining points on the earth's surface at which the magnetic declination is the same —called also isogonal
Explore M-W
Circa 1859
First Known Use of isogonic line
circa 1859
Seen and Heard
What made you want to look up isogonic line? Please tell us where you read or heard it (including the quote, if possible).
Writing? Check your grammar now!