opalescent

adjective

1. exhibiting a play of colors like that of the opal.
2. having a milky iridescence.

adjective

1. having or emitting an iridescence like that of an opal

adj.1813, from opal + -escent. adj.

1. Resembling an opal in the display of various colors, often used to describe certain bacterial cultures.

1. Exhibiting a milky iridescence like that of opal.