copperas

American  

[kop-er-uhs] / ˈkɒp ər əs /

noun

Chemistry.

1. ferrous sulfate.

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copperas British  

/ ˈkɒpərəs /

noun

1. a less common name for ferrous sulphate

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Etymology

Origin of copperas

1400–50; late Middle English coperas, variant of Middle English coperose < Medieval Latin ( aqua ) cuprōsa copperish (water). See copper ¹, -ose ¹

Example Sentences

Early mine operators realized that they could also extract copper from copperas.

From Washington Times • Jul. 3, 2017

I jes' can't 'member 'bout de dye, but dey used copperas.

From Slave Narratives: A Folk History of Slavery in the United States From Interviews with Former Slaves: Volume I, Alabama Narratives by United States. Work Projects Administration

Green olive may be made with a little more copperas and verdigris.

From Blacker's Art of Fly Making, &c. Comprising Angling, & Dyeing of Colours, with Engravings of Salmon & Trout Flies by Blacker, William

Sumach, logwood, iron liquor, and copperas, will form a black.

From Blacker's Art of Fly Making, &c. Comprising Angling, & Dyeing of Colours, with Engravings of Salmon & Trout Flies by Blacker, William

Among other lining materials found suitable were soapstone, alumina, ammonia, copperas, starch, Epsom salts, and gypsum, paper, pulp, and alum, and a mixture of various other materials.

From Inventions in the Century by Doolittle, William Henry