What does desalination mean?
Desalination is the process of removing salt and other dissolved minerals from seawater or brackish water to produce fresh water suitable for drinking, irrigation, or industrial use. It is typically accomplished through reverse osmosis, in which water is forced through fine membranes, or through thermal distillation. The word carries a largely technical register, appearing frequently in discussions of water scarcity, infrastructure investment, and climate resilience. Desalination is especially significant in arid regions such as the Middle East, Australia, and parts of California, where natural freshwater supplies cannot meet demand. Although historically expensive and energy-intensive, improvements in membrane technology have steadily lowered costs, making desalination an increasingly important tool in securing water supplies for growing populations.
nounThe process of removing salt and other minerals from seawater or brackish water to make it fresh and usable for drinking, irrigation, or industry.
- The removal of salt and minerals from seawater or brackish water to produce fresh water.
- (More broadly) any industrial or chemical process of eliminating dissolved salts from a substance.
"The coastal city invested heavily in desalination to secure its drinking water supply during the prolonged drought."
"Saudi Arabia relies on desalination to supply most of its municipal fresh water."
"Advances in membrane technology have made desalination considerably more energy-efficient than it once was."
Rarely used in the plural; the noun is almost always uncountable, referring to a process rather than discrete instances.
"Various desalinations have been attempted over the decades to address regional water shortages."
Roughly 1% of the world's population drinks water that was once the sea — thanks to desalination plants turning oceans into tap water.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of desalination
Desalination derives from the prefix 'de-' (indicating removal) combined with 'salination', rooted in the Latin word 'sal', meaning 'salt'. The same Latin root underlies words such as 'saline' and 'salinity', and, through Old French, 'salary', which originally referred to Roman soldiers' allowances for buying salt. The term emerged in modern scientific and engineering contexts in the 20th century as large-scale water treatment became technically feasible.
Related word forms
How desalination is actually used
A technical but widely understood term, common in journalism about water policy and climate adaptation. The variant 'desalinization' is less common; 'desalination' is preferred in both British and American usage.
Easily confused with desalination
Desalination removes salt (sodium chloride) from water, while decalcification removes calcium deposits.