[dis-proh-see-uh
m, -shee-] 
| 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. |
| 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 1,407°C; boiling point 2,600°C; specific gravity 8.536; valence 3. See Table at element. [New Latin, from Greek dusprositos, difficult to approach : dus-, dys- + prositos, approachable (from prosienai, to approach : pros-, toward + ienai, i-, to go; see ei- in Indo-European roots).] |
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) Pronunciation Key
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. |
dysprosium
(Dy), chemical element, rare-earth metal of the lanthanoid series of the periodic table. A relatively hard and very reactive metal, it is oxidized by air and by water. Its high melting point and ability to absorb neutrons make it useful in control rods for nuclear reactors. Its compounds have been used for making laser materials, as components in some electronic equipment, and as phosphor activators
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