Meaning of thallium in English:


(also Tl)

Pronunciation /ˈθalɪəm/


mass noun
  • 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.

    ‘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.’
    • ‘When too much thallium circulates in the blood, it invades all the organs of the body, impairing their operation, destroying hair follicles, muscles, and nerves.’
    • ‘Over-exposure to thallium may cause nerve damage, emotional changes, cramps, convulsions and eventually coma which can lead to death caused by respiratory paralysis.’


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