noun
thallium
THA-lee-uhm
Thallium (noun) means a soft, gray metallic chemical element (symbol Tl, atomic number 81) that tarnishes quickly in air and is highly toxic. Example: “Thallium was once used in rat poison before its toxicity led to bans.”
noun
1
A soft, gray metallic chemical element (symbol Tl, atomic number 81) that tarnishes quickly in air and is highly toxic.
"Thallium was once used in rat poison before its toxicity led to bans."
"The lab handled the thallium sample with extreme care."
How to use thallium
Learner’s notesIn plain EnglishA poisonous gray metal used mainly in electronics and, historically, poisons.
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Word forms
- Plural
- thalliums
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_____ was once used in rat poison before its toxicity led to bans.
Etymology
Named from Greek thallos, "green shoot," because the element produces a bright green line in its spectrum.
Synonyms
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Tl
atomic number 81
Related words
Rhymes for thallium
See all rhymes for thallium →Frequently asked questions
What does “thallium” mean?
The word “thallium” means a soft, gray metallic chemical element (symbol Tl, atomic number 81) that tarnishes quickly in air and is highly toxic. In plain terms, a poisonous gray metal used mainly in electronics and, historically, poisons.
How do you pronounce “thallium”?
“Thallium” is pronounced THA-lee-uhm (/ˈθæliəm/ in IPA).
How do you use “thallium” in a sentence?
Here is “thallium” used in a sentence: “Thallium was once used in rat poison before its toxicity led to bans.”
What part of speech is “thallium”?
“Thallium” is a noun.
Where does the word “thallium” come from?
The word “thallium” comes from Greek. Named from Greek thallos, "green shoot," because the element produces a bright green line in its spectrum.
