|1.||a. a colourless exceptionally hard mineral (but often tinted yellow, orange, blue, brown, or black by impurities), found in certain igneous rocks (esp the kimberlites of South Africa). It is used as a gemstone, as an abrasive, and on the working edges of cutting tools. Composition: carbon. Formula: C. Crystal structure: cubic|
|b. (as modifier): a diamond ring Related: diamantine|
|a. a figure having four sides of equal length forming two acute angles and two obtuse angles; rhombus|
|b. (modifier) rhombic|
|3.||a. a red lozenge-shaped symbol on a playing card|
|b. a card with one or more of these symbols or (when plural) the suit of cards so marked|
|a. the whole playing field|
|b. the square formed by the four bases|
|5.||(formerly) a size of printer's type approximately equal to 4½ point|
|6.||black diamond a figurative name for coal|
|a. an unpolished diamond|
|b. a person of fine character who lacks refinement and polish|
|8.||(tr) to decorate with or as with diamonds|
|[C13: from Old French diamant, from Medieval Latin diamas, modification of Latin adamas the hardest iron or steel, diamond; see |
|diamond (dī'ə-mənd) Pronunciation Key
A form of pure carbon that occurs naturally as a clear, cubic crystal and is the hardest of all known minerals. It often occurs as octahedrons with rounded edges and curved surfaces. Diamond forms under conditions of extreme temperature and pressure and is most commonly found in volcanic breccias and in alluvial deposits. Poorly formed diamonds are used in abrasives and in industrial cutting tools.
Someone or something with potential or talent but lacking training or polish: “Her singing voice is beautiful, but she needs help with her gestures; she's a diamond in the rough.” This phrase refers to the fact that diamonds found in nature are rough and uneven. They must be cut and polished to bring out their true beauty.
(1.) A precious gem (Heb. yahalom', in allusion to its hardness), otherwise unknown, the sixth, i.e., the third in the second row, in the breastplate of the high priest, with the name of Naphtali engraven on it (Ex. 28:18; 39:11; R.V. marg., "sardonyx.") (2.) A precious stone (Heb. shamir', a sharp point) mentioned in Jer. 17:1. From its hardness it was used for cutting and perforating other minerals. It is rendered "adamant" (q.v.) in Ezek. 3:9, Zech. 7:12. It is the hardest and most valuable of precious stones.
diamond in the rough
Also, a rough diamond. A person of exceptional character or potential but lacking polish and refinement. For example, Jack is intelligent and trustworthy but lacks mannershe's a diamond in the rough. [Early 1600s]