Function: noun
Date: circa 1859
: 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
Function: noun
Date: circa 1859
: 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
Merriam Webster Collegiate English Dictionary. Merriam Webster - Энциклопедический словарь английского языка. 2012