/ Dictionary / Index I isthmian: Meaning and Definition of Find definitions for: isth•mi•an Pronunciation: (is'mē-un), [key] — adj. of or pertaining to an isthmus. (cap.) of or pertaining to the Isthmus of Corinth or the Isthmus of Panama. —n. a native or inhabitant of an isthmus. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: isthmian (Thesaurus) Isth. Isthmian Games Related Content Daily Word Quiz: acquiesce Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language