law of constant proportion law of conservation of matter • law of continuation · · · Info · Definitions · Synonyms · Characters · · law of constant proportion · · Text Common · · Latin · · Scripts 26 · · Length 7 · · Syllables Definitions · · · (noun) (chemistry) law stating that every pure substance always contains the same elements combined in the same proportions by weight. Synonyms: law of constant proportion, law of definite proportions. · · Noun Definition 1 Synonyms · · · law of definite proportions · · Synonym 1 Characters · · space U+0020 a latin small letter a U+0061 c latin small letter c U+0063 f latin small letter f U+0066 i latin small letter i U+0069 l latin small letter l U+006C n latin small letter n U+006E o latin small letter o U+006F p latin small letter p U+0070 r latin small letter r U+0072 s latin small letter s U+0073 t latin small letter t U+0074 w latin small letter w U+0077