This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

n. A hard, brittle metallic element, found associated with nickel, silver, lead, copper, and iron ores and resembling nickel and iron in appearance. It is used chiefly for magnetic alloys, high-temperature alloys, and in the form of its salts for blue glass and ceramic pigments. 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 Table at element.

n. A chemical element (symbol Co) with an atomic number of 27.

n. Cobalt blue.

n. A tough, lustrous, reddish white metal of the iron group, not easily fusible, and somewhat magnetic. Atomic weight 59.1. Symbol Co.

n. A commercial name of a crude arsenic used as fly poison.

n. Chemical symbol, Co; atomic weight, 58.8. A metal of a steel-gray color and a specific gravity variously given at from 8.52 to 8.95.

n. a hard ferromagnetic silver-white bivalent or trivalent metallic element; a trace element in plant and animal nutrition

"In sixth grade, I started my own class newspaper, which my friends and I typed laboriously on the old fashionedmimeographsheets (the kind with the blue backing which left those same stubby fingers smudged in cobalt ink)."

metallic element    metal   

cobalt yellow    gray cobalt    cobalt blue    cobalt glass    cobalt plating    cobalt green    earthy cobalt    tin-white cobalt    glass of cobalt    erythrite   

cobalt 60   

molybdenum    chromium    nickel    magnesium    bismuth    titanium    barium    boron    uranium    arsenic