osmium Meaning, Definition & Usage

  1. noun a hard brittle blue-grey or blue-black metallic element that is one of the platinum metals; the heaviest metal known
    atomic number 76; Os.

WordNet

Os"mi*um noun
Etymology
Gr. a smell, odor, akin to to smell. So named in allusion to the strong chlorinelike odor of osmic tetroxide. See Odor.
Definitions
  1. (Chem.) A rare metallic element of the platinum group, found native as an alloy in platinum ore, and in iridosmine. It is a hard, infusible, bluish or grayish white metal, and the heaviest substance known. Its tetroxide is used in histological experiments to stain tissues. Symbol Os. Atomic weight 191.1. Specific gravity 22.477.

Webster 1913