a soft malleable highly toxic white metallic element used as a rodent and insect poison and in low-melting glass. Its compounds are used as infrared detectors and in photoelectric cells. Symbol: Tl; atomic no: 81; atomic wt: 204.3833; valency: 1 or 3; relative density: 11.85; melting pt: 304°C; boiling pt: 1473±10°C
Word origin
C19: from New Latin, from Greek thallos a green shoot; referring to the green line in its spectrum
thallium in American English
(ˈθæliəm)
noun
a rare, poisonous, bluish-gray, soft, metallic chemical element, used in making photoelectric cells,rat poisons, etc.: symbol, Tl; at. no. 81
Word origin
ModL: so named by Crookes, its discoverer < Gr thallos, young, green shoot (< thallein: see Thalia) because of its green spectral line
Examples of 'thallium' in a sentence
thallium
Still, they'll have to do the thallium scan and maybe cardiac catheter.