thallium

noun

thal·​li·​um ˈtha-lē-əm How to pronounce thallium (audio)
: a soft poisonous metallic element that resembles lead in physical properties, occurs sparsely in a number of common ores, and is used chiefly in the form of compounds especially in photosensitive devices and formerly as a pesticide see Chemical Elements Table

Examples of thallium in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Testing by the utility identified selenium and thallium in the effluent there. Connor Giffin, The Courier-Journal, 23 Jan. 2024 But the spotlight naturally pulls back to Beck, whose eidetic memory for faces, locations and even a stray box of thallium salts at the crime scene suggests a level of expertise honed in places far beyond Lincoln County. Paula L. Woods, Los Angeles Times, 18 July 2023 While other metals such as nickel, thallium and lead were more likely to exceed those EPA markers in poorer, less-white communities like Rose Park, arsenic was more concentrated in samples from wealthy communities, possibly because of its past use as a fertilizer on agricultural lands. Evan Bush, NBC News, 7 Dec. 2022 Check out thallium and tungsten. Ed Yong, Discover Magazine, 24 Sep. 2011 See all Example Sentences for thallium 

Word History

Etymology

New Latin, from Greek thallos green shoot; from the bright green line in its spectrum

First Known Use

1861, in the meaning defined above

Time Traveler
The first known use of thallium was in 1861

Dictionary Entries Near thallium

Cite this Entry

“Thallium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thallium. Accessed 25 Dec. 2024.

Kids Definition

thallium

noun
thal·​li·​um ˈthal-ē-əm How to pronounce thallium (audio)
: a soft poisonous metallic element that has characteristics similar to lead see element

Medical Definition

thallium

noun
thal·​li·​um ˈthal-ē-əm How to pronounce thallium (audio)
: a sparsely but widely distributed poisonous metallic element that resembles lead in physical properties and is used chiefly in the form of compounds in photoelectric cells or as a pesticide
symbol Tl
see Chemical Elements Table

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