Thallium
/ˈθæliəm/noun
A soft, toxic chemical element with the symbol Tl and atomic number 81.
Did you know?Thallium was named in 1861 by William Crookes from Greek thallos, because of the bright green line it showed in spectroscopy—proof that even a poison can wear a “living” color.
Etymological Timeline
Ancient Greek
Greek
θάλλος (thállos)
“a green shoot, twig, or young branch”
1861
English
thallium
“newly identified element named for its green spectral line”
Modern English
English
thallium
“the chemical element Tl, a highly toxic metal”
Modern Scientific Latin
Latin
thallium
“scientific name formed from Greek thallos”