the milky iridescent appearance of a dense transparent medium when it is illuminated by polychromatic visible radiation (such as sunlight) due to local fluctuations in its density and therefore in its refractive index
the property of combined refraction and reflection of light, resulting in smoky tints
the trait of a white surface having iridescence and resembles the colors in an opal
Opalescent means colourless or white like an opal, or changing colour like an opal. Elaine turned her opalescent eyes on him. a sky which was still faintly opalescent. + opalescence opal·es·cence The sunset was making great splashes of fiery opalescence across the sky. having colours that shine and seem to change
having a play of lustrous rainbow-like colors; "an iridescent oil slick"; "nacreous (or pearlescent) clouds looking like mother-of-pearl"; "a milky opalescent (or opaline) luster"