/ Dictionary / Index I isogonal line: Meaning and Definition of Find definitions for: isog'onal line' Pronunciation: (ī'su-gōn"), [key] an imaginary line, or one drawn on a map, connecting all points of equal magnetic declination. Also called isoganal, i&syl;so&syl;goneisogonic. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. isogonal isogonic Related Content Daily Word Quiz: penchant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language