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cobalt

[ koh-bawlt ]
/ ˈkoʊ bɔlt /
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noun
a silver-white metallic element with a faint pinkish tinge, occurring in compounds whose silicates afford important blue coloring substances for ceramics. Symbol: Co; atomic weight: 58.933; atomic number: 27; specific gravity: 8.9 at 20°C.

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Origin of cobalt

1675–85; <German Kobalt, variant of Koboldkobold
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use cobalt in a sentence

British Dictionary definitions for cobalt

cobalt
/ (ˈkəʊbɔːlt) /

noun
a brittle hard silvery-white element that is a ferromagnetic metal: occurs principally in cobaltite and smaltite and is widely used in alloys. The radioisotope cobalt-60, with a half-life of 5.3 years, is used in radiotherapy and as a tracer. Symbol: Co; atomic no: 27; atomic wt: 58.93320; valency: 2 or 3; relative density: 8.9; melting pt: 1495°C; boiling pt: 2928°C

Word Origin for cobalt

C17: German Kobalt, from Middle High German kobolt goblin; from the miners' belief that malicious goblins placed it in the silver ore
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for cobalt

cobalt
[ kōbôlt′ ]

Co
A silvery-white, hard, brittle metallic element that occurs widely in metal ores. It is used to make magnetic alloys, heat-resistant alloys, and blue pigment for ceramics and glass. Atomic number 27; atomic weight 58.9332; melting point 1,495°C; boiling point 2,900°C; specific gravity 8.9; valence 2, 3. See Periodic Table.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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