Definition of diamond in English:

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Pronunciation: /ˈdī(ə)mənd/


1A precious stone consisting of a clear and typically colorless crystalline form of pure carbon, the hardest naturally occurring substance.
Example sentences
  • Boucheron won the day, and will be auctioning an exquisite brooch of diamonds, rock crystal, topaz and emeralds, with the cash donated to the new foundation.
  • Gemstones such as diamonds, opals, sapphires, and rubies are produced in Brazil.
  • The country is also blessed with plenty of precious minerals such as diamonds, gold, emeralds, amethyst which are all waiting to be exploited.
1.1A tool with a small diamond for cutting glass.
Example sentences
  • One of these was a diamond crusted circular saw for cutting rocks.
  • The appropriate mathematical function of the asphere must simply be loaded into the control system for the diamond tool to follow as it cuts across the surface.
  • Can't cut it with any of our tools, even the diamond laser, without completely shattering it beyond use.

Diamonds occur in some igneous rock formations (kimberlite) and alluvial deposits. They are typically octahedral in shape but can be cut in many ways to enhance the internal reflection and refraction of light, producing jewels of sparkling brilliance. Diamonds are also used in cutting tools and abrasives.

2 [often as modifier] A figure with four straight sides of equal length forming two opposite acute angles and two opposite obtuse angles; a rhombus: decorative diamond shapes
More example sentences
  • Score the inner side in a diamond pattern with the tip of a small, sharp knife and then cut into 5cm / 2inch squares.
  • When trying to widen a space, square tiles should be laid in a diamond pattern and rectangular tiles should be laid in a brick or herringbone pattern.
  • She looked overhead and noticed on top of the clock tower, a giant crystal, not as round or red as the one the ship, but a triangular blue diamond shape.
2.1 (diamonds) One of the four suits in a conventional deck of playing cards, denoted by a red diamond.
Example sentences
  • This is a valid tractor because four in a suit other than diamonds is the next rank above ace.
  • Because of the difference in score, clubs and diamonds are called the minor suits and hearts and spades are the major suits.
  • The familiar suits of hearts, diamonds, clubs and spades were introduced by French cardmakers in the late fifteenth century.
2.2A playing card of the suit of diamonds: she led a losing diamond
More example sentences
  • Regardless of the suit a joker played ‘high’ will defeat any diamond.
  • The six cards in each fail suit are ranked like the six lowest diamonds.
2.3The area delimited by the four bases of a baseball field, forming a square shape.
Example sentences
  • I agree with the idea of having each one of the four buttons on the gamepad correspond to their respective bases on the baseball diamond.
  • The Mets would love to add Furcal, even though they would have to convince him to move to the right on the infield diamond and play second base.
  • The playing area is delineated by two perpendicular lines that converge at the home plate, the focus point of the diamond made up of four bases - home, first, second and third.
2.4A baseball field.
Example sentences
  • Baseball diamonds were bustling with activity all weekend as there were 44 registered teams competing.
  • Enter ABC skate shop and the baseball diamond at Tompkin's Square.
  • There's an area in front of the baseball diamonds and soccer fields for Frisbee golf.


diamond in the rough

North American A person who is generally of good character but lacks manners, education, or style.
Example sentences
  • He may even be this year's NBA diamond in the rough.
  • He is a diamond in the rough who showed flashes last year with the Browns.
  • In his perennial search for diamonds in the rough, GM Jerry West brought in three second round picks.



Pronunciation: /ˌdīmənˈdif(ə)rəs/
Example sentences
  • More recently, modern exploration has resulted in the reported identification of uneconomic though diamondiferous kimberlites in Iron and Dickinson Counties in northern Michigan.
  • In recent years, submerged diamondiferous deposits, of mostly latest Quaternary age, lying on the continental shelf off the West Coast of southern Africa have attracted a great deal of economic and geological interest.
  • The results from exploration by the company since project commencement during mid 1999 are considered to be very encouraging for the discovery of diamondiferous kimberlite source rocks.


Middle English: from Old French diamant, from medieval Latin diamas, diamant-, variant of Latin adamans (see adamant).

  • The name of the gem derives from a medieval Latin alteration of Latin adamans adamant. Adamant was a legendary rock or mineral with many supposed properties. One of these was hardness, which was a reason why people sometimes identified it with diamond. A diamond is forever was used as an advertising slogan for De Beers Consolidated Mines from the late 1940s onwards, and in 1956 Ian Fleming used Diamonds are Forever as the title of his latest James Bond thriller, but the idea was first expressed by the American writer Anita Loos, in Gentlemen Prefer Blondes (1925). ‘Diamonds are a Girl's Best Friend’ was a song written by Leo Robin and Jule Styne for the 1949 stage musical of Gentlemen Prefer Blondes.

For editors and proofreaders

Syllabification: dia·mond

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