yttrium

noun

yt·​tri·​um ˈi-trē-əm 

: a metallic element with atomic number 39 usually included in the rare-earth group that occurs usually with other rare earth elements in minerals and is used especially in phosphors, YAG lasers, alloys, and treatments for certain cancers see Chemical Elements Table

Examples of yttrium in a Sentence

Recent Examples on the Web

Interest in rare earths—comprising 15 lanthanides and scandium and yttrium, which are critical for modern technologies, such as artificial intelligence—is rising amid trade disputes between the U.S. and China. —Ryan Chan, MSNBC Newsweek, 15 Aug. 2025

The reactors use the superconducting tape, which is typically made of yttrium barium copper oxide, in powerful electromagnets. —IEEE Spectrum, 26 June 2025

Today, yttrium is used in lighting and flat screens; ytterbium in cancer treatments and earthquake monitoring; erbium in lasers and fiberoptic cables. —Charlie Campbell, Time, 17 June 2025

Europe sourced almost 90% of its yttrium in 2023 — a rare earth element used in the manufacturing of fighter jets, land vehicles and targeting systems — from China, according to Morningstar. —Chloe Taylor, CNBC, 11 June 2025

Word History

Etymology

New Latin, from yttria yttrium oxide (Y₂O₃), irregular from Ytterby, town in southern Sweden

First Known Use

1814, in the meaning defined above

Kids Definition

yttrium

noun

yt·​tri·​um ˈi-trē-əm 

: a metallic element that occurs in minerals along with other similar uncommon elements see element

Medical Definition

yttrium

noun

yt·​tri·​um ˈi-trē-əm 

: a trivalent metallic element usually included among the rare earth elements which it resembles chemically and with which it occurs in minerals

—symbol Y see Chemical Elements Table