Definition of thallium in English:

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Pronunciation: /ˈTHalēəm/


The chemical element of atomic number 81, a soft silvery-white metal that occurs naturally in small amounts in pyrite and other ores. Its compounds are very poisonous. (Symbol: Tl)
Example sentences
  • However, water-soluble rubidium, cesium, thallium, and silver minerals are virtually nonexistent and should pose no complication.
  • The scintillation detector, in this case a crystal of sodium iodide doped with thallium, emits a number of photons in direct proportion to the amount of energy deposited in the crystal by the dark matter particle.
  • My advice is to undergo another test called stress thallium, which will show the amount of involvement of the heart muscle with ischemia.


Mid 19th century: modern Latin, from Greek thallos 'green shoot', because of the green line in its spectrum.

Words that rhyme with thallium

allium, gallium, pallium, valium

For editors and proofreaders

Syllabification: thal·li·um

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