ENGLISH
REFERENCE

cobalt

n. uncountable
C1 Advanced US //ˈkoʊˌbɔɫt// UK //kˈəʊbɒlt// cobalt

n. a hard, silver-gray metal used to make strong materials and batteries. It is also famous for creating a deep, beautiful blue color in glass and paint.

n. a hard, brittle, silvery-white magnetic metal element, often used in high-strength alloys and lithium-ion batteries. Also refers to a deep blue pigment or color derived from its salts.


SIMPLE

The artist used cobalt to paint the deep blue sky.

CONTEXTUAL

Manufacturers require large amounts of cobalt to produce the rechargeable batteries found in modern electric vehicles.

COMPLEX

The transition to renewable energy has significantly increased the global demand for cobalt, leading to intensified mining operations in regions with rich mineral deposits.

Synonyms
Origin

From German Kobalt, formerly also Kobald, ‑olt, ‑old, ‑elt, ‑el, apparently the same word as Kobold (“goblin”), from Middle High German, which became also a Harz Mountains silver miners’ term for rock laced with arsenic and sulfur, so called because it degraded the ore and made the miners ill. Doublet of kobold.

Usage

Uncountable when referring to the chemical element or the color; countable only when referring to specific isotopes or chemical compounds in a laboratory context.

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