breastbone breastbeam • breasted · · · Info · Definitions · Synonyms · Characters · · breastbone · · Text Latin · · Script 10 · · Length Definitions · · · (noun) the flat bone that articulates with the clavicles and the first seven pairs of ribs. Synonyms: sternum. · · Noun Definition 1 Synonyms · · · sternum · · Synonym 1 Characters · · a latin small letter a U+0061 b latin small letter b U+0062 e latin small letter e U+0065 n latin small letter n U+006E o latin small letter o U+006F r latin small letter r U+0072 s latin small letter s U+0073 t latin small letter t U+0074