/ Thesaurus / I Synonyms of isogonal line Find synonyms for: Noun1. isogonic line, isogonal line, isogone, lineusage: an imaginary line connecting points on the Earth's surface where the magnetic declination is the sameWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: penury Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language