Breadcrumb Home > Dictionary > Index B breastsummer: Meaning and Definition of Find definitions for: breast•sum•mer Pronunciation: (bres'sum"ur, brest'-, bres'u-mur), [key] — n. Archit. a horizontal beam supporting an exterior wall over an opening, as a shop window. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. breaststroke breast timber ✖ Related Content Daily Word Quiz: hortatory Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language