diamond

The word “diamond” means an extremely hard, clear crystal form of carbon, prized as a gemstone. In plain terms, a hard, sparkling gemstone; also the four-sided card suit and rhombus shape named after it.

“Diamond” is pronounced DEYE-uh-muhnd (/ˈdaɪ.ə.mənd/ in IPA).

Here is “diamond” used in a sentence: “She was proposed to with a ring set with a single diamond.”

Depending on how it is used, “diamond” can be a noun and an adjective.

The word “diamond” comes from Latin. From Old French diamant, from Latin adamas ("hardest metal"), from Greek adamas — the same root as "adamant." Diamond and adamant are doublets.

“Diamond” is a fairly common word in modern English, usually learned at around the A2 level.

“Diamond” has 5 distinct senses listed in this dictionary. The most common is: an extremely hard, clear crystal form of carbon, prized as a gemstone.

A diamond is a natural crystal of pure carbon and the hardest known natural material. Cubic zirconia is a man-made stone that imitates a diamond's appearance but is softer, cheaper, and throws off more rainbow-colored flashes. A jeweler can tell the two apart quite easily.

Chemically and physically they are the same — both are real diamonds made of crystallized carbon with identical hardness and sparkle. The only difference is origin: a natural diamond forms in the earth over millions of years, while a lab-grown one is created in weeks, usually at a lower price.

Each carbon atom bonds tightly to four neighbors in a rigid three-dimensional lattice, making the whole crystal extremely strong and difficult to scratch. This structure places diamond at the very top of the Mohs hardness scale, so in practice only another diamond can easily scratch it.

Cut, color, clarity, and carat weight. Cut governs how much a stone sparkles, color grades how colorless it is, clarity measures internal flaws, and carat is the weight. Together the four Cs determine a diamond's overall quality and, in turn, its price.