platinum

UK: /ˈplætɪnəm/

US: /ˈplætənəm, ˈplætnəm/

US: (plat′n əm, plat′nəm)

WordReference Random House Learner's Dictionary of American English © 2026

plat•i•num /ˈplætənəm, ˈplætnəm/   n. [uncountable]

1. Chemistry a heavy, grayish-white, metallic chemical element, resistant to most chemicals, that can be easily shaped and that conducts electricity.
2. a light gray color with some blue.

adj. 

3. Music, Music and Dance (of a recording or record album) having sold a minimum of two million single records or one million LPs.
4. of the color of platinum;
   grayish-white with some blue.

WordReference Random House Unabridged Dictionary of American English © 2026

plat•i•num  (plat′n əm, plat′nəm), n. 

1. 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;
   at. wt.: 195.09;
   at. no.: 78;
   sp. gr.: 21.5 at 20°C.
2. a light, metallic gray with very slight bluish tinge when compared with silver.

adj. 

3. Chemistry made of platinum.
4. 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/ noun

1. 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

adjective

1. (prenominal) denoting the 70th in a series, esp an annual series: a platinum jubilee

Etymology: 19th Century: New Latin, from platina, on the model of other metals with the suffix -um