Medical Dictionary
red tide
noun
Medical Definition of RED TIDE
: seawater discolored by the presence of large numbers of dinoflagellates especially of the genera Gonyaulax and Gymnodinium which produce a toxin poisonous especially to many forms of marine vertebrate life and to humans who consume contaminated shellfish—see paralytic shellfish poisoning; compare saxitoxin
Seen & Heard
What made you want to look up red tide? Please tell us where you read or heard it (including the quote, if possible).