black diamond

American  

noun

1. carbonado.

2. black diamonds, coal.

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black diamond British  

noun

1. another name for carbonado 2

2. (usually plural) a figurative expression for coal

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Etymology

Origin of black diamond

First recorded in 1910–15

Example Sentences

Accompanied by specially-trained truffle dogs, foodies get dirt under their nails as they dig for these stinky “black diamonds.”

From Salon

For those whose knees go weak at the sight of black diamonds, plenty of intermediate areas feature gentler groomed trails.

From The Wall Street Journal

Deaf Ski and Snowboard Assn. — was going down a single black diamond trail when he pulled over to the side to stop, the lawsuit said.

From Los Angeles Times

Ferdinand the Bull is an easy, hand-built blue square with one black diamond option.

From Seattle Times

Once the Summit Express gets the green light, a cornucopia of black and double black diamond runs comes into play.

From Seattle Times