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

Recent Examples of red tide from the Web

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First Known Use of red tide

1904


Medical Dictionary

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 GirardeauCalypso Log DispatchOctober 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 BakalarThe New York Times16 Jan. 2007
— see brevetoxin, saxitoxin, shellfish poisoning

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