Definition of molecular weight in English:

molecular weight


  • The ratio of the average mass of one molecule of an element or compound to one twelfth of the mass of an atom of carbon-12.

    ‘Milk protein, or casein, is a mixture of molecules with molecular weights ranging from 75,000 to 375,000 daltons (amu).’
    • ‘The ethyl group has a greater molecular weight than the smallest alkyl radical which is the methyl group.’
    • ‘Alcohols and ethers having higher molecular weights do not dissolve well in water, however, because the water molecules can not completely surround those molecules.’
    • ‘During these reactions, they are chemically linked forming macromolecules, or polymers, which have large molecular weights.’
    • ‘Although this is adequate for some common proteins, it is useless for, say, enzyme complexes that commonly have molecular weights of 5 MDa or more.’


molecular weight

/məˌlekyələr ˈwāt/ /məˌlɛkjələr ˈweɪt/