lu·​te·​tium lü-ˈtē-sh(ē-)əm How to pronounce lutetium (audio)
: a metallic chemical element of the rare-earth group that has few practical applications but is sometimes used as a catalyst in cracking and as a radiation source for treatment of certain cancers see Chemical Elements Table

Examples of lutetium in a Sentence

Recent Examples on the Web The team at Rochester started with a small, thin foil of lutetium, a silvery white metal that is among the rarest of rare earth elements, and pressed it between two interlocking diamonds. Kenneth Chang, New York Times, 8 Mar. 2023 Salamat has used imaging methods that reveal where the heavy lutetium atoms are within the compound, but the team isn’t yet certain about the configuration of the lighter hydrogen and nitrogen atoms. Sophie Bushwick, Scientific American, 10 Mar. 2023 For the past few years, Dias’ team has worked on a superhydride based on lutetium. Quanta Magazine, 8 Mar. 2023 The results, published today in Nature, appear to show that a conventional conductor — a solid composed of hydrogen, nitrogen and the rare-earth metal lutetium — was transformed into a flawless material capable of conducting electricity with perfect efficiency. Quanta Magazine, 8 Mar. 2023 The research team zeroed in on lutetium based on the fact that the occupancy of its electron orbitals should provide a few more electrons that could potentially participate in forming Cooper pairs, possibly making superconductivity easier. John Timmer, Ars Technica, 8 Mar. 2023 The new material is made from the rare earth metal lutetium baked in a gas mixture of 99 percent hydrogen and 1 percent nitrogen. Peter Weber, The Week, 9 Mar. 2023 To produce a sample, the team would bathe a thin film of lutetium in a perfume of 99% hydrogen and 1% nitrogen while baking it for a few days at 200 degrees Celsius. Quanta Magazine, 8 Mar. 2023 The new superconductor consists of lutetium, a rare earth metal, and hydrogen with a little bit of nitrogen mixed in. Kenneth Chang, New York Times, 8 Mar. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'lutetium.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


New Latin, from Latin Lutetia, ancient name of Paris

First Known Use

1907, in the meaning defined above

Time Traveler
The first known use of lutetium was in 1907

Dictionary Entries Near lutetium

Cite this Entry

“Lutetium.” Dictionary, Merriam-Webster, Accessed 4 Oct. 2023.

Kids Definition


lu·​te·​tium lü-ˈtē-sh(ē-)əm How to pronounce lutetium (audio)
: a soft metallic chemical element see element

Medical Definition


variants also lutecium
: a metallic element of the rare-earth group
symbol Lu
see Chemical Elements Table

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