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lanthanum Line breaks: lan|thanum
Pronunciation: /ˈlanθənəm/

Definition of lanthanum in English:


[mass noun]
The chemical element of atomic number 57, a silvery-white rare earth metal. (Symbol: La)
Example sentences
  • It belongs to the family known as the lanthanides, named after the first member of that series, lanthanum.
  • Green light is also emitted from some lanthanide elements: lanthanum, cerium, and terbium.
  • Oxalate efflux could not be triggered by treatment with the trivalent cation lanthanum or by phosphorus deficiency, indicating that the efflux was specific to the Al treatment.


Mid 19th century: from Greek lanthanein 'escape notice' (because it was long undetected in cerium oxide) + -um.

Words that rhyme with lanthanum

philtrum • outcome • sugarplum

Definition of lanthanum in:

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