Milliosmoles

Part of speech: noun

Definitions

1. A unit of osmotic concentration equal to one thousandth of an osmole, used to measure solute levels in body fluids
2. A measurement unit for the concentration of dissolved particles, equal to a thousandth of an osmole, commonly applied in medicine and chemistry
3. The thousandth part of an osmole, a unit expressing how many osmotically active particles are dissolved in a given solution

Etymology: "Milliosmoles" is the plural of "milliosmole," a unit used in chemistry and medicine to measure osmotic concentration, equal to one thousandth of an osmole. The word is built from two parts: the prefix "milli-," from Latin "mille" meaning thousand, and "osmole," itself a compound of "osmosis" and "mole," the unit of amount of substance. The "mole" in that name comes from the Latin "moles," meaning a mass or bulk, a sense that was later applied to a fixed quantity of particles. Because the osmole is a measure of the number of dissolved particles in a solution rather than of their mass, a single unit describes how strongly a fluid draws water across a membrane. Clinicians use milliosmoles per kilogram to report the concentration of blood plasma and urine, so the plural form appears in everyday laboratory results.