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 southwest Florida over the past week, a months-long bloom of red tide has been blamed for respiratory irritations and dead fish, turtles and manatees. Jennifer Kay, OrlandoSentinel.com, "Blue-green algae, red tide soil beaches, threaten Florida tourism," 10 July 2018 In 2017, state wildlife officials blamed red tide for a spike in manatee deaths. Jenny Staletovich, miamiherald, "Waters off Florida Keys hit with rare red tide. It’s prime suspect in fish kills | Miami Herald," 1 Mar. 2018 The track was recorded for Copa Airlines as a send-off for the national team, known as la marea roja (the red tide). Billboard Staff, Billboard, "2018 World Cup: Hear Anthems for Argentina, Brazil, Mexico, Spain, Panama and More," 13 June 2018 Scripps scientist Michael Latz said the red tide is due to massive numbers of dinoflagellates including Lingulodinium polyedra. CBS News, "Bioluminescence from red tide: Algae bloom literally lighting up San Diego waves at night," 9 May 2018 There are organisms in the red tide that glow when they’re stirred up by things like breaking waves. Gary Robbins, sandiegouniontribune.com, "You've got to see this new video of the surf glowing off La Jolla due to bioluminesence," 11 May 2018 The breathtaking light show began on Monday when patches of red tide began to appear along the coast. Gary Robbins, sandiegouniontribune.com, "You've got to see this new video of the surf glowing off La Jolla due to bioluminesence," 11 May 2018 The rare phenomenon on Southern California's West Coast is known as the red tide. CBS News, "Bioluminescence from red tide: Algae bloom literally lighting up San Diego waves at night," 9 May 2018 Periods are undeniably one of the most dreaded parts of any month, but with November comes a good reason to get excited about the red tide for a change. Sadé Carpenter, RedEye Chicago, "Thinx kicks off Fearless Bleeding Tour in Chicago," 31 Oct. 2017

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.

See More

First Known Use of red tide

1904, in the meaning defined above

Keep scrolling for more

Learn More about red tide

Statistics for red tide

Look-up Popularity

Time Traveler for red tide

The first known use of red tide was in 1904

See more words from the same year

Keep scrolling for more

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, Calypso Log Dispatch, October 1984 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, The New York Times, 16 Jan. 2007 — see brevetoxin, saxitoxin, shellfish poisoning

More from Merriam-Webster on red tide

See words that rhyme with red tide

Britannica.com: Encyclopedia article about red tide

Comments on red tide

What made you want to look up red tide? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

to reject or criticize sharply

Get Word of the Day daily email!

Test Your Vocabulary

Words from Greek and Roman Mythology Quiz

  • the-triumph-of-venus-by-alessandro-magnasco
  • Boreal comes from the name of the ancient Greek god of which wind?
Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ
Bee Cubed

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!