a black powder consisting of very finely divided metallic platinum, used as a catalyst, especially in organic synthesis.
Origin of platinum black
First recorded in 1850–55
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
chem a black powder consisting of very finely divided platinum metal. It is used as a catalyst, esp in hydrogenation reactions
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012