The chemical element of atomic number 81, a soft silvery-white metal which occurs naturally in small amounts in iron pyrites, sphalerite, and other ores. Its compounds are very poisonous. (Symbol: Tl)
More 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.
Definition of thallium in:
- The US English dictionary