say it: AHZ-mee-uhm
osmium is a noun meaning "a hard brittle blue-grey or blue-black metallic element that is one of the platinum metals; the heaviest metal known". It carries one recorded sense.
a hard brittle blue-grey or blue-black metallic element that is one of the platinum metals; the heaviest metal known
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for osmium come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.