Word Study
thulium
CIDE DICTIONARY
thulium, n. [NL. See Thule.].
A rare metallic element of uncertain properties and identity, said to have been found in the mineral gadolinite. [1913 Webster]
OXFORD DICTIONARY
thulium, n. Chem. a soft metallic element of the lanthanide series, occurring naturally in apatite.
Usage
Symb.: Tm.
Etymology
mod.L f. L Thule name of a region in the remote north
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