What is the meaning of Rainbow?

A multicoloured arch in the sky, produced by prismatic refraction of light within droplets of rain in the air.

Any prismatic refraction of light showing a spectrum of colours.

A wide assortment; a varied multitude.

An illusion; a mirage.

A curveball, particularly a slow one.

In Texas hold 'em or Omaha hold 'em, a flop that contains three different suits.

Rainbow trout.

A person within the LGBT community.

Multicolored, especially if in rainbow order.

Made up of several races or ethnicities, or (more broadly) of several cultural or ideological factions.

LGBT.

Composed entirely of different suits.

Of or pertaining to rainbow tables.

To brighten with, or as with, a rainbow; to pattern with the colours of the rainbow.

To take the appearance of a rainbow.

In climbing gyms where the rocks to climb are colored to indicate suggested climbing routes, to climb rocks of different colors, thereby ignoring such routes.

Source: wiktionary.org