noun
Etymology: isogonic (I)
: an imaginary line or a line on a map joining points on the earth's surface at which magnetic declination is the same — compare aclinic line , agonic line
noun
Etymology: isogonic (I)
: an imaginary line or a line on a map joining points on the earth's surface at which magnetic declination is the same — compare aclinic line , agonic line
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012