/ Dictionary / Index R rhodium: Meaning and Definition of Find definitions for: rho•di•um Pronunciation: (rō'dē-um), [key] — n. Chem. a silvery-white metallic element of the platinum family, forming salts that give rose-colored solutions: used to electroplate microscopes and instrument parts to prevent corrosion. Symbol: Rh; at. wt.: 102.905; at. no.: 45; sp. gr.: 12.5 at 20°C. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: rhodium (Thesaurus) rhodic rhodo- Related Content Daily Word Quiz: careening Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language