Saline: When Salt Becomes Medicine
Saline means salty. In medicine it names a sterile salt solution that matches the body's own concentration, and it is one of the most used fluids in hospitals.
Saline means containing salt. In a hospital it means something very precise: a sterile solution of about nine grams of sodium chloride per litre, close enough to the concentration of blood that cells neither swell nor shrink in it. That single unremarkable fluid is among the most administered substances in medicine.
- Salty, containing salt. *A saline lake.*
- A medical salt solution. *A saline drip.*
- Saline drift — salt buildup in soil. *Saline soils cut yields.*
- Salinity — how salty something is. *Ocean salinity.*
Word forms
| Form | Word | Example |
|---|---|---|
| Adjective | saline | Saline water. |
| Noun | saline | A litre of saline. |
| Abstract | salinity | Rising salinity. |
| Verb | salinise | Irrigation salinises soil. |
| Related | brine | Olives in brine. |
- She was put on a saline drip overnight.Medical.
- The lake is more saline than the sea.Geography.
- Salinity in the estuary changes with the tide.The abstract noun.
Degrees of saltiness
- Fresh — under about 0.5 grams of salt per litre
- Brackish — between fresh and sea water, as in an estuary
- Saline — around the saltiness of the sea, or of blood in medical use
- Brine — heavily saturated, used for curing
- Hypersaline — saltier than the ocean, as in the Dead Sea
From Latin *salinus*, from *sal*, salt. English used it for salt springs and salt works from the 1400s; the medical sense is nineteenth-century.
Why is medical saline 0.9 per cent?
Because that concentration is close to the salt content of blood plasma, so red blood cells keep their normal shape in it.
Is saline the same as salt water?
In everyday terms yes, but medical saline is sterile and made to an exact concentration, which ordinary salt water is not.