platinum

1. The chemical element with atomic number 78 and symbol Pt; a dense, malleable, ductile, highly unreactive, silverish-white transition metal of great value. (countable, uncountable)
2. A whitish grey colour, like that of the metal. (countable, uncountable)
3. A single or album that has achieved platinum sales, i.e. over 1 million or 2 million. (countable)
4. A platinum-based drug: a platin. (countable)

Plural platinums