What does euryhaline mean?
Euryhaline is an adjective used almost exclusively in biology and ecology to describe aquatic organisms that can tolerate a wide range of salt concentrations in their environment. A euryhaline fish, for example, may live comfortably in a freshwater river, a brackish estuary, or full-strength seawater — a flexibility that allows species such as salmon, bull sharks, and mummichogs to migrate between habitats that would kill most other fish. The word comes from Greek roots meaning 'broad' (eury-) and 'salt' (haline), so it literally means 'wide-salted'. Its opposite is stenohaline, describing organisms restricted to a narrow salinity band. The term is indispensable to discussions of osmoregulation, estuarine ecology, and aquaculture, where knowing whether a species is euryhaline determines how and where it can be kept or studied.
adjectiveAble to tolerate a wide range of salinities in the surrounding water; used chiefly of aquatic organisms that thrive in both fresh and salt water.
- (Of aquatic organisms) capable of tolerating a wide range of water salinities.
"The mummichog is a famously euryhaline fish, flourishing everywhere from freshwater marshes to full-strength seawater."
"Euryhaline species such as tilapia can be farmed successfully in both freshwater and brackish ponds."
"Because bull sharks are euryhaline, they have been recorded thousands of miles up the Amazon River."
Salmon are born in rivers, roam the open ocean, and swim back upstream to spawn — all because they're euryhaline.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of euryhaline
Euryhaline was formed in the nineteenth century from two combining forms of Greek origin: 'eury-', from Greek eurys meaning 'wide' or 'broad', and '-haline', from Greek hals meaning 'salt'. The same salt root appears in words such as halogen and halite, while the eury- prefix recurs in scientific terms like eurythermal. The term arose as biologists needed precise language to classify aquatic life by its tolerance of salinity, pairing it with its opposite, stenohaline.
Related word forms
How euryhaline is actually used
A technical term used mainly in biology, ecology, fisheries science, and aquaculture rather than everyday speech; it carries no figurative or informal usage.
Easily confused with euryhaline
Stenohaline describes organisms that can survive only within a narrow range of salinity, the exact opposite of euryhaline.