co·​balt | \ˈkō-ˌbȯlt \

Definition of cobalt 

1 : a tough lustrous silver-white magnetic metallic element that is related to and occurs with iron and nickel and is used especially in alloys — see Chemical Elements Table

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Did You Know?

The metallic element "cobalt" ultimately draws its name from folklore. In Middle High German, "kobolt" denoted a usually helpful household elf that engaged in nasty pranks only when it was offended. Later, early Modern German Kobold came to refer to a variety of less helpful goblins inhabiting fields and mountains. The variant "Kobolt" in the 16th century was applied by German miners to ores containing the metal cobalt, which they considered to be worthless; they believed that mountain goblins had spoiled adjacent silver ores, or had stolen the silver within the ore. The metal itself in relatively pure form was not produced and described until the 17th century, when "cobalt," with its first letter influenced by New Latin cobaltum, became part of the international language of science.

Examples of cobalt in a Sentence

Recent Examples on the Web

The changes will raise taxes and other costs for operators in Congo, which is Africa’s top copper producer and the world’s main source of cobalt, a critical ingredient in rechargeable batteries., "Congo President Set to Approve Law Changes Despite Miners' Pleas," 7 Mar. 2018 Glencore, through its Congolese mines, is the world’s biggest producer of cobalt, a key commodity for electric-vehicle batteries. Scott Patterson, WSJ, "Glencore to Resume Payments to Sanctioned Billionaire Gertler," 15 June 2018 The key is that the blue in question is neither basic navy nor that glaring cobalt every #menswear blogger in Pitti obsessed over at the beginning of the decade. Yang-yi Goh, GQ, "The Best Affordable Suit For Your Non-Stop Summer Schedule," 29 June 2018 So Goodenough made the cobalt himself, heating the precursors at very high temperatures. Ellen Airhart, WIRED, "Alternatives to Cobalt, the Blood Diamond of Batteries," 7 June 2018 The best-selling shades are Otherworldly (a violet/cobalt/magenta/copper) and Heavenly (a maroon/gold/olive). Devon Abelman, Allure, "These Color-Changing Pigments Are Like Expert Eye Shadow Blending Skills in a Jar," 21 Mar. 2018 Finding a way to recycle lithium-ion batteries on a large scale could greatly reduce the demand — as well as curb the rising cots — for cobalt in electric vehicles. Rob Nikolewski,, "UCSD professor devises way to recycle lithium-ion batteries," 16 Mar. 2018 Apple might buy cobalt directly from miners for the first time., "Five Things You Need to Know to Start Your Day," 21 Feb. 2018 As lithium-ion batteries become more prevalent in electric cars and other devices, cobalt has seen its value rise as a commodity. David Grossman, Popular Mechanics, "Mining Company Buys Rights to Former National Monument Land," 21 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cobalt.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of cobalt

1683, in the meaning defined at sense 1

History and Etymology for cobalt

German Kobalt, alteration of Kobold, literally, goblin, from Middle High German kobolt; from its occurrence in silver ore, believed to be due to goblins

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cobalt 60


cobalt bloom

Statistics for cobalt

Last Updated

10 Nov 2018

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Time Traveler for cobalt

The first known use of cobalt was in 1683

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More Definitions for cobalt



English Language Learners Definition of cobalt

: a hard, shiny, silver-white metal that is often mixed with other metals


co·​balt | \ˈkō-ˌbȯlt \

Kids Definition of cobalt

: a tough shiny silvery white metallic chemical element found with iron and nickel


co·​balt | \ˈkō-ˌbȯlt \

Medical Definition of cobalt 

: a tough lustrous silver-white magnetic metallic element that is related to and occurs with iron and nickel and is used especially in alloys symbol Co — see Chemical Elements Table

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