- Chemistry. a heavy, grayish-white, highly malleable and ductile metallic element, resistant to most chemicals, practically unoxidizable except in the presence of bases, and fusible only at extremely high temperatures: used for making chemical and scientific apparatus, as a catalyst in the oxidation of ammonia to nitric acid, and in jewelry. Symbol: Pt; atomic weight: 195.09; atomic number: 78; specific gravity: 21.5 at 20°C.
- a light, metallic gray with very slight bluish tinge when compared with silver.
- made of platinum.
- (of an audio recording) having sold a minimum of one million copies.
Origin of platinum
Examples from the Web for platinum
He also earned a Grammy and platinum record for “Up Where We Belong.”The Greatest Rock Voice of All Time Belonged to Joe Cocker
December 23, 2014
Delta is a Platinum Global Partner, ranking them among the highest-level contributors to the association.How You Can Help Make a More LGBT-Friendly World
December 12, 2014
A platinum plan pays 90 percent of costs; gold plans pay 80 percent; silver plans pay 70 percent; bronze pay 60 percent.
For platinum, gold, or other more generous plans, the premiums (or amount you pay up front) will be more expensive.
She had gathered her platinum hair loosely in a black scrunchie.From Baltimore Ravens Cheerleader to Mrs. Robinson
November 6, 2014
About her neck was a chain of blue stones linked with platinum.City of Endless Night
Anybody can be liberal if someone else furnishes the platinum.Mixed Faces
“Good thing she has platinum crosshairs,” he said to Ashton.Out of the Depths
Robert Ames Bennet
The metal which possesses this property to the highest degree, is platinum.Practical Mechanics for Boys
J. S. Zerbe
Only platinum could exist there, and the matter had to rearrange itself as platinum.Invaders from the Infinite
John Wood Campbell
- a ductile malleable silvery-white metallic element, very resistant to heat and chemicals. It occurs free and in association with other platinum metals, esp in osmiridium: used in jewellery, laboratory apparatus, electrical contacts, dentistry, electroplating, and as a catalyst. Symbol: Pt; atomic no: 78; atomic wt: 195.08; valency: 1–4; relative density: 21.45; melting pt: 1769°C; boiling pt: 3827±100°C
- a medium to light grey colour
- (as adjective)a platinum carpet
Word Origin and History for platinum
metallic element, 1812, Modern Latin, from Spanish platina "platinum," diminutive of plata "silver," from Old French plate or Old Provençal plata "sheet of metal" (see plate (n.)). The metal looks like silver, and the Spaniards at first thought it an inferior sort of silver, hence the name platina. It was first obtained from Spanish colonies in Mexico and Colombia, brought to Europe in 1735, and identified as an element 1741. Taken into English as platina (c.1750), it took its modern form (with element ending -ium) in 1812, at the time the names of elements were being regularized. As a shade of blond hair, attested from 1931. As a designation for a recording that has sold at least one million copies, it is attested from 1971.
- A ductile malleable metallic element usually occurring mixed with other metals such as iridium, osmium, or nickel and used as a catalyst and in dentistry. Atomic number 78.
- A soft, ductile, malleable, silver-white metallic element that usually occurs with osmium, iridium, palladium, or nickel. It has a high melting point and does not corrode in air. Platinum is used as a catalyst and in making jewelry, electrical contacts, and dental crowns. Atomic number 78; atomic weight 195.08; melting point 1,772°C; boiling point 3,827°C; specific gravity 21.45; valence 2, 3, 4. See Periodic Table.