/ Dictionary / Index B boundary condition: Meaning and Definition of Find definitions for: bound'ary condi"tion Pronunciation: [key] — Math. Math. a stated restriction, usually in the form of an equation, that limits the possible solutions to a differential equation. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. boundary boundary layer Related Content Daily Word Quiz: supine Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language