| 释义 |
WordReference Random House Learner's Dictionary of American English © 2024plat•i•num /ˈplætənəm, ˈplætnəm/USA pronunciation n. [uncountable]- Chemistrya heavy, grayish-white, metallic chemical element, resistant to most chemicals, that can be easily shaped and that conducts electricity.
- a light gray color with some blue.
adj. - Music, Music and Dance(of a recording or record album) having sold a minimum of two million single records or one million LPs.
- of the color of platinum;
grayish-white with some blue.
WordReference Random House Unabridged Dictionary of American English © 2024plat•i•num (plat′n əm, plat′nəm),USA pronunciation n. - Chemistrya 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;
at. wt.: 195.09;
at. no.: 78;
sp. gr.: 21.5 at 20°C. - a light, metallic gray with very slight bluish tinge when compared with silver.
adj. - Chemistrymade of platinum.
- Music, Music and Dance(of a record, CD, or cassette) having sold a minimum of one million copies.
- Spanish; see platina
- Neo-Latin, alteration of earlier platina
- 1805–15
Collins Concise English Dictionary © HarperCollins Publishers:: platinum /ˈplætɪnəm/ n - 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
Etymology: 19th Century: New Latin, from platina, on the model of other metals with the suffix -um |