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

In recent years, the state’s coasts and waterways have been besieged by outbreaks of blue-green algae and red tide that have killed marine life and driven away tourists. Arian Campo-flores, WSJ, "New Florida Governor Moves Quickly With Supreme Court Pick, Environmental Plan," 10 Jan. 2019 But the incidences of red tides seem to have increased since the 1950s and 1960s. Kate Furby, The Seattle Times, "Red tide algae’s deadly toll on sea life has triggered a state of emergency in Florida," 14 Aug. 2018 Known as a red tide, the algae bloom produces toxic chemicals that can affect the central nervous systems of fish and other animals, killing or impairing them. Arian Campo-flores, WSJ, "Why the Red Tide Is Killing Florida’s Sea Turtles," 29 July 2018 The red tides are unpredictable and not all produce a bioluminescence. CBS News, "Bioluminescence from red tide: Algae bloom literally lighting up San Diego waves at night," 9 May 2018 The decree is not involved with other water problems that plagued Florida coasts last year, including red tide outbreaks and algae blooms. Curt Anderson, The Seattle Times, "Judge won’t end decades-old Everglades cleanup oversight," 11 Feb. 2019 Environmental concerns have been a major issue in the campaign because of an outbreak of blue-green algae and red tide, which produces toxic chemicals blamed for killing fish, sea turtles, dolphins and other animals. Arian Campo-flores, WSJ, "Florida Senate Seat Becomes Year’s Most Expensive Race," 26 Oct. 2018 The current red tide has lasted about a year so far, the longest stretch in more than a decade, and has spread from the west coast to the east, hurting the tourism industry. Arian Campo-flores, WSJ, "Florida Senate Seat Becomes Year’s Most Expensive Race," 26 Oct. 2018 For humans, red tide can cause respiratory irritation to those on shore, itchy skin or a burning sensation in the eyes of swimmers. Sebastian Modak, Condé Nast Traveler, "Florida Hit By Worst 'Red Tide' Bloom in Over a Decade," 3 Aug. 2018

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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1 Jun 2019

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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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