/ Dictionary / Index M meridian circle: Meaning and Definition of Find definitions for: merid'ian cir"cle Pronunciation: [key] a transit instrument provided with a graduated vertical scale, used to measure the declinations of heavenly bodies and to determine the time of meridian transits. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. meridian angle méridienne 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