heavy water heavy swell • heavy weapon · · · Info · Definitions · Synonyms · Characters · · heavy water · · Text Common · · Latin · · Scripts 11 · · Length 4 · · Syllables Definitions · · · (noun) water containing a substantial proportion of deuterium atoms, used in nuclear reactors. Synonyms: heavy water, deuterium oxide. · · Noun Definition 1 Synonyms · · · deuterium oxide · · Synonym 1 Characters · · space U+0020 a latin small letter a U+0061 e latin small letter e U+0065 h latin small letter h U+0068 r latin small letter r U+0072 t latin small letter t U+0074 v latin small letter v U+0076 w latin small letter w U+0077 y latin small letter y U+0079