OPALESCENT

iridescent, nacreous, opalescent, opaline, pearlescent

(adjective) having a play of lustrous rainbow colors; “an iridescent oil slick”; “nacreous (or pearlescent) clouds looking like mother-of-pearl”; “a milky opalescent (or opaline) luster”

Source: WordNet® 3.1

Etymology

Adjective

opalescent (comparative more opalescent, superlative most opalescent)

Exhibiting a milky iridescence like that of an opal.

Source: Wiktionary

O`pal*es"cent, a.

Definition: Reflecting a milky or pearly light from the interior; having an opaline play of colors.

Source: Webster’s Unabridged Dictionary 1913 Edition