| IRIDESCENCE | Play of rainbow colours |
| OPAL | Forming around hot springs, unique for its play of rainbow colours and found in art deco jewellery, the national gemstone of Australia (4) |
| OPALESCENCE | A milky play of rainbow colours |
| OPALINE | Milk glass; or, pertaining to a gem with a unique play of rainbow colours, a word for nacreous, iridescent, pearly, polychromatic or prismatic (7) |
| SPECTRUM | Band of rainbow colours (8) |
| PRISMS | Polyhedrons, such as the transparent crystal or glass bodies that separate white light into spectra of rainbow colours (6) |
| IRIDESCENT | Description of an object with a play of lustrous rainbow colours, such as a soap bubble, mother-of-pearl-lined shell, peacock's feather or butterfly's wing (10) |
| NONPAREIL | Word for something regarded as unequalled, such as a painted bunting; a fine russet apple; or, one of "hundreds and thousands" of rainbow- coloured sprinkles used to decorate a chocolate button of the |
| ROYGBIV | Mnemonic for rainbow colours |
| PRISM | Crystal shaped to disperse light in rainbow colours |
| TREE | Jeremy ...., trainer of Rainbow Quest, winner of the 1985 Prix de l'Arc de Triomphe (4) |
| UTAH | Locale of Rainbow Bridge |
| OWN | Personal slice of rainbow nation (3) |
| IRIS | Greek goddess of rainbow |
| ARC | Patrick regularly observed quality of rainbow (3) |
| OMAHA | Setting of Rainbow Rowell's novel "Eleanor & Park" |
| TRACEEELLISROSS | Portrayer of Rainbow Johnson on "Black-ish" |
| OPALS | Gems with glints of rainbow color |
| RENEW | Extend sides of rainbow about 67.5 degrees? |
| DRE | Nickname of Rainbow's husband on "Black-ish" |
