red tide
noun
: seawater discolored by the presence of large numbers of dinoflagellates (as of the genera Karenia, Gymnodinium, and Alexandrium) which typically produce a toxin poisonous especially to many forms of marine vertebrate life and to humans who consume contaminated shellfish compare saxitoxin
Examples of red tide in a Sentence
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The agency reported that testing for parasites, bacteria, viruses and more than 250 chemicals, as well as checks for such issues as toxic red tide, turned up nothing definitive.
—
Curt Anderson, Sun Sentinel, 5 Mar. 2025
There are new fears about an outbreak of red tide dampening the winter tourism season.
—Jennifer Reed, New York Times, 26 Feb. 2025
In Collier and Pinellas Counties the level of red tide is unlikely to cause health issues.
—Josh Hammer, Newsweek, 17 Feb. 2025
But a surge in deaths in recent years – much of which has been blamed on poor water quality, algae blooms, increasingly busier waters and red tide – has led officials to consider whether the manatee should again be considered endangered.
—Christopher Cann, USA TODAY, 30 Dec. 2024
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Curt Anderson, Sun Sentinel, 5 Mar. 2025
There are new fears about an outbreak of red tide dampening the winter tourism season.
—Jennifer Reed, New York Times, 26 Feb. 2025
In Collier and Pinellas Counties the level of red tide is unlikely to cause health issues.
—Josh Hammer, Newsweek, 17 Feb. 2025
But a surge in deaths in recent years – much of which has been blamed on poor water quality, algae blooms, increasingly busier waters and red tide – has led officials to consider whether the manatee should again be considered endangered.
—Christopher Cann, USA TODAY, 30 Dec. 2024
See All Example Sentences for red tide
Cite this Entry
“Red tide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/red%20tide. Accessed 16 Mar. 2025.
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red tide
noun
: a large area of seawater discolored by the presence of large numbers of dinoflagellates (as of the genera Karenia, Gymnodinium, and Alexandrium) which typically produce toxins poisonous especially to many forms of vertebrate marine life and to humans who consume contaminated shellfish
In simple terms, a red tide is a dinoflagellate population explosion, caused when certain species "bloom," or multiply many times faster than usual.—Ellen Girardeau
Ellen GirardeauRed tides, the blooms of toxic Karenia brevis algae that appear almost every year in Florida, often lasting for months and turning the ocean red, may be dangerous to asthma sufferers—even if they don't go swimming.—Nicholas Bakalar
see brevetoxin, saxitoxin, shellfish poisoning
Nicholas BakalarLove words? Need even more definitions?
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