atrium of the heart atrium dextrum • atrium sinistrum · · · Info · Definitions · Synonyms · Characters · · atrium of the heart · · Text Common · · Latin · · Scripts 19 · · Length 6 · · Syllables Definitions · · · (noun) the upper chamber of each half of the heart. Synonyms: atrium cordis, atrium of the heart. · · Noun Definition 1 Synonyms · · · atrium cordis · · Synonym 1 Characters · · space U+0020 a latin small letter a U+0061 e latin small letter e U+0065 f latin small letter f U+0066 h latin small letter h U+0068 i latin small letter i U+0069 m latin small letter m U+006D o latin small letter o U+006F r latin small letter r U+0072 t latin small letter t U+0074 u latin small letter u U+0075