copper sulfate


: a sulfate of copper
especially : the normal sulfate that is white in the anhydrous form but blue in the crystalline hydrous form CuSO4·5H2O and that is often used as an algicide and fungicide

Example Sentences

Recent Examples on the Web But the microbes don’t just clean the copper sulfate up. Joshua Learn, Discover Magazine, 5 May 2021 In their recommendations to Parliament in 1999, the Committee on European Communities noted that copper sulfate, in particular, was far more dangerous than the synthetic alternative. Christie Wilcox, Discover Magazine, 24 Sep. 2012 The Division of Forestry, Fire and State Lands, which manages the contracts to mitigate algal blooms in the state’s public lands, primarily uses copper sulfate as an algaecide, the division’s interim director, Jamie Barnes, said. The Salt Lake Tribune, 2 Aug. 2021 In the study, researchers from the U and the U.S. Geological Survey applied a copper sulfate solution to the water in St. Alban's Bay near Excelsior. Katy Read, Star Tribune, 4 Nov. 2020 In the 1950s, scientists tried using copper sulfate. Jenny Howard, National Geographic, 5 July 2019 The European Union determined that copper sulfate may cause cancer and intended to ban it, but backed off because organic farmers don’t have any viable alternative. Henry I. Miller, WSJ, 5 Aug. 2018 One that organic gardeners all over the world know is the fungicide Bordeaux mix, with copper sulfate as the main ingredient. Jo Ellen Meyers Sharp, Indianapolis Star, 13 July 2018 See More

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

Word History

First Known Use

1869, in the meaning defined above

Time Traveler
The first known use of copper sulfate was in 1869

Dictionary Entries Near copper sulfate

Cite this Entry

“Copper sulfate.” Dictionary, Merriam-Webster, Accessed 20 Mar. 2023.

Kids Definition

copper sulfate

: a usually blue crystalline compound that is used to destroy algae and fungi

Medical Definition

copper sulfate

: a sulfate of bivalent copper that is best known as the blue crystalline hydrate CuSO4·5H2O, is used as an algicide and fungicide, and has been used medicinally in solution as an emetic but is not now recommended for such use because of its potential toxicity

called also cupric sulfate

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