say it: LUH-struhs
lustrous is an adjective meaning "made smooth and bright by or as if by rubbing; reflecting a sheen or glow". It is pronounced /ˈlʌstɹəs/ — LUH-struhs. It carries 3 recorded senses.
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 lustrous 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.