Definition of osmolality in US English:



  • The concentration of a solution expressed as the total number of solute particles per kilogram.

    • ‘The infusion should be diluted to reduce the osmolality, even if an increase in infusion rate is necessary.’
    • ‘The important factors in the production of phlebitis by amino acid solutions were osmolality and the amount of potassium infused per day.’
    • ‘To obtain a direct measurement of the osmolality, 50 randomly selected samples were analyzed with an osmometer.’
    • ‘The osmolality of all prepared solutions was measured with an osmometer.’
    • ‘They are also regulatory organs, controlling the volume and the composition of the body fluids and maintaining the correct osmolality, ion concentrations, and acid - base status of the body.’


1950s: blend of osmotic (see osmosis) and molal, + -ity.