rainbow

Literally speaking, a rainbow is an arc (bow) of colors that appears in the sky due to rays of sunshine being reflected and refracted by raindrops (or other water droplets). The word rainbow is also commonly used to refer to any artistic representations of this.

Technically speaking, a rainbow can be classified as a primary rainbow or a secondary rainbow. Together, they can form a double rainbow. Triple rainbows are very rare.

Rainbow is also commonly used as an adjective that means containing all or many colors of the spectrum (the main ones being red, orange, yellow, green, blue, indigo, and violet—aka roygbiv). Synonyms of this sense include multicolored (or multicolor), kaleidoscopic, and prismatic. Kaleidoscopic suggests something full of bright colors in a way that’s reminiscent of the images seen when looking through a kaleidoscope. Prismatic is a reference to the rainbow-colored when light shines through a prism.

Extended from this is a more general sense of rainbow that’s applied to anything featuring a diverse collection of people or things, as in rainbow coalition.

Rainbows and rainbow flags are popularly used as symbols of the LGBTQ+ community.

Sunshine and rainbows is an idiom used to refer a situation that’s completely positive in all aspects. The phrase is most often used in negative constructions to imply that such situations are rare or impossible (and that it’s naive to think that they’re not), as in Marriage is not all sunshine and rainbows.

Phrases used to mean the same thing often use some of the same terms in varying combinations: sunshine and lollipops, unicorns and rainbows, sunshine and puppies.

The phrase peaches and cream can mean the same thing, but it’s more often used in positive constructions.

The phrase sweetness and light is somewhat similar, but it’s usually applied to people, as opposed to situations.

Singles words that can mean the same thing are rosy and rose-colored.