red tide

noun

Definition of red tide

: 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

Recent Examples on the Web Warmer waters also lead to algae blooms, red tides that further decrease oxygen, and kill sea life. Jen Christensen, CNN, "Fish are in trouble with the climate crisis, IPCC report finds," 25 Sep. 2019 Topical exposure to red tides in water can irritate human respiratory systems, as well as the skin, eyes, nose and throat. Talal Ansari, WSJ, "Florida’s Red Tide Killed At Least 174 Dolphins," 27 June 2019 Brevetoxin is produced by blooms of Karenia Brevis, commonly known as red tide. Emily Atkin, The New Republic, "The Frightening Spread of Toxic Algae," 28 Aug. 2019 After 2018’s high ecological toll, red tide is at normal background levels this year. USA TODAY, "Charlottesville remembered, drive-thru ban, ketchup karma: News from around our 50 states," 13 Aug. 2019 Manatee deaths soared in 2018, with a lot of deaths attributed to red tide, but boat deaths made up only 65 of the 444 total halfway through the year. Richard Tribou, orlandosentinel.com, "Boat-related manatee deaths surge in 2019," 15 July 2019 In August 2018, former Florida Gov. Rick Scott declared a state of emergency in several counties as the red tide disrupted the state’s tourism industry. Talal Ansari, WSJ, "Florida’s Red Tide Killed At Least 174 Dolphins," 27 June 2019 The red tide was declared an emergency by Florida Gov. Rick Scott on Monday. James Rogers, Fox News, "Blue-green toxic algae invades Florida river," 15 Aug. 2018 The red tides, in turn, are worsened by climate change, scientists say. Chris Mooney, Anchorage Daily News, "Large parts of the globe have already passed a crucial climate threshold," 11 Sep. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'red tide.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of red tide

1904, in the meaning defined above

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Last Updated

16 Nov 2019

Time Traveler for red tide

The first known use of red tide was in 1904

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More Definitions for red tide

red tide

noun

Medical Definition of red tide

: 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 Red 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

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