nacreous
1. [ adjective ] consisting of or resembling mother-of-pearl
Related terms: mother-of-pearl
2. [ adjective ] (color) having a play of lustrous rainbow-like colors
Synonyms: opalescent pearlescent opaline iridescent
Examples:

"an iridescent oil slick" "nacreous (or pearlescent) clouds looking like mother-of-pearl" "a milky opalescent (or opaline) luster"

Related terms: bright