/ Dictionary / Index A acleistocardia: Meaning and Definition of Find definitions for: a•cleis•to•car•di•a Pronunciation: (u-klī"stu-kär'dē-u, ā-klī"-), [key] — n. Pathol. a failure of the foramen ovale of the heart to close. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. acle aclinic line Related Content Daily Word Quiz: arboreal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language