noun, often attributive \ˈdī-(ə-)mənd\

: a very hard usually colorless stone that is a form of carbon and is used especially in jewelry

: a shape that is formed by four equal straight lines and that has two opposite angles that are smaller than a right angle and two opposite angles that are larger than a right angle

: a playing card that is marked with a red diamond shape

Full Definition of DIAMOND

a :  native crystalline carbon that is the hardest known mineral, that is usually nearly colorless, that when transparent and free from flaws is highly valued as a precious stone, and that is used industrially especially as an abrasive; also :  a piece of this substance
b :  crystallized carbon produced artificially
:  something that resembles a diamond (as in brilliance, value, or fine quality)
:  a square or rhombus-shaped figure usually oriented with the long diagonal vertical
a :  a playing card marked with a stylized figure of a red diamond
b plural but sing or plural in constr :  the suit comprising cards marked with diamonds
:  a baseball infield; also :  the entire playing field

Examples of DIAMOND

  1. a necklace studded with diamonds and rubies
  2. The ruby was surrounded by a ring of diamond.
  3. The children cut the fabric into diamonds.
  4. one heart, two diamonds, and two clubs
  5. He played the queen of diamonds.

Origin of DIAMOND

Middle English diamaunde, from Middle French diamand, from Late Latin diamant-, diamas, alteration of Latin adamant-, adamas hardest metal, diamond, from Greek
First Known Use: 14th century



Definition of DIAMOND

transitive verb
:  to adorn with or as if with diamonds

First Known Use of DIAMOND




: of or relating to the 60th or 75th anniversary of an important event (such as a marriage)

Full Definition of DIAMOND

:  of, relating to, or being a 60th or 75th anniversary or its celebration <diamond jubilee>

Examples of DIAMOND

  1. the celebration of Queen Victoria's diamond jubilee in 1897

First Known Use of DIAMOND



biographical name \ˈdī-(ə-)mənd\

Definition of DIAMOND

Peter A(rthur) 1940– Am. econ.


geographical name \ˈdī-(ə-)mənd\

Definition of DIAMOND

mountains SE North Korea; highest 5374 feet (1638 m)

Variants of DIAMOND

Di·a·mond or Kum·gang \ˈkm-ˌgäŋ\


noun    (Concise Encyclopedia)

Mineral composed of pure carbon, the hardest naturally occurring substance known and a valuable gemstone. Diamonds are formed deep in the Earth by tremendous pressures and temperatures over long periods of time. In the crystal structure of diamond, each carbon atom is linked to four other, equidistant, carbon atoms. This tight crystal structure results in properties that are very different from those of graphite, the other common form of pure carbon. Diamonds vary from colourless to black and may be transparent, translucent, or opaque. Most gem diamonds are transparent and colourless or nearly so. Colourless or pale blue stones are most valued, but most gem diamonds are tinged with yellow. Because of their extreme hardness, diamonds have important industrial applications. Most industrial diamonds are gray or brown and are translucent or opaque. In the symbolism of gemstones, the diamond represents steadfast love and is the birthstone for April.


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