Dysprosium

[dis-proh-see-uh m, -shee-] /dɪsˈproʊ si əm, -ʃi-/

noun, Chemistry.
1.
a rare-earth metallic element, highly reactive and paramagnetic, found in small amounts in various rare-earth minerals, as euxenite and monazite: used to absorb neutrons in nuclear reactors. Symbol: Dy; atomic weight: 162.50; atomic number: 66.
/dɪsˈprəʊsɪəm/
noun
1.
a soft silvery-white metallic element of the lanthanide series: used in laser materials and as a neutron absorber in nuclear control rods. Symbol: Dy; atomic no: 66; atomic wt: 162.50; valency: 3; relative density: 8.551; melting pt: 1412°C; boiling pt: 2567°C
n.

element, obtained 1906 from an earth discovered in 1886, the last to be extracted from the complex earth called yttria, and named dysprosia in reference to the difficulty of obtaining it, from Greek dysprositos “hard to get at, difficult of access,” from dys- “bad” (see dys-) + prositos “approachable.” With metallic element suffix -ium.

dysprosium dys·pro·si·um (dĭs-prō’zē-əm, -zhē-əm)
n.
Symbol Dy
A soft, silvery rare-earth element used in nuclear research. Atomic number 66; atomic weight 162.50; melting point 1,411°C; boiling point 2,600°C; specific gravity 8.551; valence 3.
dysprosium
(dĭs-prō’zē-əm)
Symbol Dy
A soft, silvery metallic element of the lanthanide series. Because it has a high melting point and absorbs neutrons well, dysprosium is used to help control nuclear reactions. Atomic number 66; atomic weight 162.50; melting point 1,407°C; boiling point 2,600°C; specific gravity 8.536; valence 3. See Periodic Table.