reverse osmosis

American  

noun

Chemistry.

1. the process in which pure water is produced by forcing waste or saline water through a semipermeable membrane.

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reverse osmosis British  

noun

1. a technique for purifying water, in which pressure is applied to force liquid through a semipermeable membrane in the opposite direction to that in normal osmosis

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reverse osmosis Scientific  

1. A method of producing pure water by forcing saline or impure water through a semipermeable membrane across which salts or impurities cannot pass. Reverse osmosis is used for water filtration, for desalinization of seawater, and in kidney dialysis machines.

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Etymology

Origin of reverse osmosis

First recorded in 1950–55

Compare meaning

How does reverse-osmosis compare to similar and commonly confused words? Explore the most common comparisons:

• osmosis vs. reverse osmosis

Example Sentences

Pitcher filters are simple, but their long-term cost can be higher than that of adsorption or reverse osmosis filters installed under the sink.

From Salon

Typically, he added, they can be treated using activated carbon and reverse osmosis.

From Los Angeles Times

A massive sewage recycling program purifies wastewater through microfiltration, reverse osmosis and ultraviolet irradiation, adding to drinking supply reservoirs.

From Seattle Times

However, the amount of PET was dwarfed by the amount of polyamides, a form of nylon used in the reverse osmosis filters that water is run through before bottling.

From Los Angeles Times

Rather than the liquid flowing through the membrane head-on, reverse osmosis uses cross-flow filtration.

From Salon