Calomel

n. white powder containing mercury (used as a laxative and as an antiseptic)

Mercury(I) chloride is the chemical compound with the formula Hg2Cl2. Also known as calomel or mercurous chloride, this dense white or yellowish-white, odorless solid is the principal example of a mercury(I) compound. It is a component of reference electrodes in electrochemistry.
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Noun
1. a tasteless colorless powder used medicinally as a cathartic
(synonym) mercurous chloride
(hypernym) chloride
(substance-holonym) blackwash, black lotion
(substance-meronym) mercury, quicksilver, hydrargyrum, Hg, atomic number 80

n. calomel, white powder containing mercury

n. calomel, white powder containing mercury (used as a laxative and as an antiseptic)