ar·​se·​nic | \ ˈärs-nik, ˈär-sə- How to pronounce arsenic (audio) \

Definition of arsenic

 (Entry 1 of 2)

1 : a solid chemical element that is used especially in wood preservatives, alloys, and semiconductors and is extremely toxic in both pure and combined forms — see Chemical Elements Table
2 : a poisonous trioxide As2O3 or As4O6 of arsenic used especially as an insecticide or weed killer

called also arsenic trioxide


ar·​sen·​ic | \ är-ˈse-nik How to pronounce arsenic (audio) \

Definition of arsenic (Entry 2 of 2)

: of, relating to, or containing arsenic especially with a valence of five

Examples of arsenic in a Sentence

Recent Examples on the Web: Noun The report calls out Beech-Nut for an incomplete recall of its infant rice cereal products that tested over the Food and Drug Administration's limit for inorganic arsenic. Taylor Avery, USA TODAY, 1 Oct. 2021 The documents showed some products contained levels of lead, mercury, cadmium and inorganic arsenic were far above limits set for bottled water by the FDA and the US Environmental Protection Agency. Sandee Lamotte, CNN, 29 Sep. 2021 Arsenic is a naturally occurring element in the environment that can enter the food supply through soil, water or air, and most of the time, concerning levels of arsenic are not found in food, according to the FDA. Michelle Shen, USA TODAY, 12 Oct. 2021 The maximum level for inorganic arsenic in bottled water, for comparison, is 10 parts per billion. Taylor Avery, USA TODAY, 1 Oct. 2021 People with unusually high exposure to inorganic arsenic, which can occur naturally or as a result of pollution, may experience nausea, vomiting, diarrhea or dehydration, according to the CDC. Dallas News, 30 July 2021 Additionally, varying levels of arsenic can be found in foods like rice and some fish. Stefani Sassos, Ms, Rdn, Cso, Good Housekeeping, 13 Sep. 2020 Consuming inorganic arsenic has been associated with cancer, skin lesions, cardiovascular diseases and diabetes. Sandee Lamotte And Gisela Crespo, CNN, 6 Aug. 2020 According to Healthy Babies Bright Futures, the lowest levels of arsenic are found in basmati rice grown in California, India and Pakistan. Sandee Lamotte And Gisela Crespo, CNN, 6 Aug. 2020 Recent Examples on the Web: Adjective Specifically, analyses have frequently found Ayurvedic treatments containing lead, arsenic, and mercury. Beth Mole, Ars Technica, 23 Feb. 2022 Try not to rely too heavily on rice cereals, as rice products can contain arsenic levels harmful to children. Washington Post, 10 Apr. 2022 One difference is obvious: The bronze in most of the tools contains a fairly large amount of arsenic, which would probably raise some eyebrows in a modern surgical suite. Kiona N. Smith, Ars Technica, 13 Apr. 2022 The following year, the state of Idaho sued the two companies that had come to share ownership of the mine, over the cobalt, copper, arsenic, and other heavy metals that had drained from the mine into Blackbird Creek and others. Michael Holtz, The Atlantic, 24 Jan. 2022 Amid reports that the soil was contaminated with lead and carcinogens, including arsenic, residents began a decades-long effort to be relocated at government expense. Washington Post, 16 Mar. 2022 Coal ash, which is the result of burning coal to make electricity, contains a dangerous mix of heavy metals and toxic chemicals such as arsenic, boron lead and mercury. Sarah Bowman, The Indianapolis Star, 10 Mar. 2022 Many rely on household wells or small water systems where the water is contaminated with chemicals or naturally occurring pollutants such as arsenic. Ian James, Los Angeles Times, 13 Feb. 2022 The singer supports men and women dealing with setbacks brought on by their surgeries, from arsenic poisoning to immense pain and more. Essence, 15 Dec. 2021 See More

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

First Known Use of arsenic


1747, in the meaning defined at sense 1


1798, in the meaning defined above

History and Etymology for arsenic


Middle English arsenek, arsenic "any of various compounds of arsenic, as yellow orpiment (arsenic trisulfide)," borrowed from Anglo-French & Latin; Anglo-French arsenik, arsneke, borrowed from Latin arrhenicum, arsenicon, borrowed from Greek arsenikón, arrhenikón, probably borrowed from Aramaic zarnīḵ "arsenic" or a cognate Semitic word, borrowed from an unattested form in a Middle Iranian language (whence Persian zarnī, zarnīk "orpiment, arsenic"), a derivative of the word for "gold" (as Manichaean Parthian zrn /zarn/ "gold," zrnyn /zarnēn/ "golden"), alluding to the yellow color of orpiment

Note: The Greek word is assumed to have been reshaped by folk-etymological association with arsenikós, arrhenikós "male, masculine." Aramaic zarnīḵ is attested in a papyrus text (an order to repair a boat) dated January, 411 b.c., found in elephantine, Egypt (see A. Cowley, Aramaic Papyri of the Fifth Century B.C., Oxford, 1923, pp. 88-97; B. Porten, The Elephantine Papyri in English: Three Millennia of Cross-Cultural Continuity and Change, Brill, 1996, pp. 115-22); the word is also attested in Syriac a number of centuries later. The Manichaean Parthian forms are from D. Durkin-Meisterernst, Dictionary of Manichaean Texts, vol. III, Part 1, Dictionary of Manichaean Middle Persian and Parthian, Brepols, 2004. Parthian zrn and zrnyn are continuations of an Old Iranian etymon represented by Avestan zarańiia- "gold"—see note at gold entry 1.


from attributive or compound use of arsenic entry 1

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The first known use of arsenic was in 1747

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Last Updated

18 May 2022

Cite this Entry

“Arsenic.” Dictionary, Merriam-Webster, Accessed 26 May. 2022.

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More Definitions for arsenic


ar·​se·​nic | \ ˈärs-nik How to pronounce arsenic (audio) , ˈär-sə- \

Kids Definition of arsenic

: a solid poisonous chemical element that is usually gray and snaps easily


ar·​se·​nic | \ ˈärs-nik, -ᵊn-ik How to pronounce arsenic (audio) \

Medical Definition of arsenic

 (Entry 1 of 2)

1 : a trivalent and pentavalent solid poisonous element that is commonly metallic steel-gray, crystalline, and brittle symbol As — see Chemical Elements Table


ar·​sen·​ic | \ är-ˈsen-ik How to pronounce arsenic (audio) \

Medical Definition of arsenic (Entry 2 of 2)

: of, relating to, or containing arsenic especially with a valence of five

More from Merriam-Webster on arsenic

Nglish: Translation of arsenic for Spanish Speakers Encyclopedia article about arsenic


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