First Known Use: 1861
Dictionary
thallium
noun thal·li·um \ˈtha-lē-əm\
Definition of THALLIUM
: a soft poisonous metallic element that resembles lead in physical properties, occurs sparsely in a number of common ores, and is used chiefly in the form of compounds especially in photosensitive devices and formerly as a pesticide — see element table
See thallium defined for kids ADVERTISEMENT
Origin of THALLIUM
New Latin, from Greek thallos green shoot; from the bright green line in its spectrum
Medical Dictionary
thallium
noun thal·li·um \ˈthal-ē-əm\
Medical Definition of THALLIUM
: a sparsely but widely distributed poisonous metallic element that resembles lead in physical properties and is used chiefly in the form of compounds in photoelectric cells or as a pesticide—symbol Tl; see element table
Learn More About THALLIUM
Browse
ADVERTISEMENT
Seen & Heard
What made you want to look up thallium? Please tell us where you read or heard it (including the quote, if possible).