praseodymium

American  

[prey-zee-oh-dim-ee-uhm, prey-see-] / ˌpreɪ zi oʊˈdɪm i əm, ˌpreɪ si- /

noun

Chemistry.

1. a rare-earth, metallic, trivalent element, named from its green salts. Pr; 140.91; 59; 6.77 at 20°C.

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praseodymium British  

/ ˌpreɪzɪəʊˈdɪmɪəm /

noun

1. a malleable ductile silvery-white element of the lanthanide series of metals. It occurs principally in monazite and bastnaesite and is used with other rare earths in carbon-arc lights and as a pigment in glass. Symbol: Pr; atomic no: 59; atomic wt: 140.90765; valency: 3; relative density: 6.773; melting pt: 931°C; boiling pt: 3520°C

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praseodymium Scientific  

/ prā′zē-ō-dĭm′ē-əm /

1. A soft, malleable, silvery metallic element of the lanthanide series that develops a green tarnish in air. It is used to add a yellow tint to glass and ceramics and to make the glass used in welding goggles. Atomic number 59; atomic weight 140.908; melting point 935°C; boiling point 3,127°C; specific gravity 6.8; valence 3, 4.

2. See Periodic Table

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Etymology

Origin of praseodymium

1880–85; < New Latin, equivalent to praseo- (combining form representing Greek prásios leek-green; see prase) + (di)dymium

Example Sentences

See Examples For:

praseodymium

The most-used rare earths are neodymium and praseodymium.

From Barron's ● May 13, 2026

Four elements account for most of the sector's economic value: neodymium, praseodymium, dysprosium and terbium.

From Barron's ● Feb. 4, 2026

Many potential investors didn’t know the importance of obscure rare-earth minerals such as praseodymium.

From The Wall Street Journal ● Oct. 27, 2025

The deal means that for the next 10 years the US government will commit to MP Materials receiving a minimum price of $110 per kg for its neodymium and praseodymium output.

From BBC ● Jul. 10, 2025

Other elements are less familiar—hafnium, erbium, dyprosium and praseodymium, say, which we do not much bump into in everyday life.

From "Cosmos" by Carl Sagan