Rainbow word meaning and definition

[noun] an illusory hope; "chasing rainbows"
[noun] an arc of colored light in the sky caused by refraction of the sun's rays by rain

\Rain"bow`\, n. [AS. regenboga, akin to G. regenbogen. See {Rain}, and {Bow} anything bent,] A bow or arch exhibiting, in concentric bands, the several colors of the spectrum, and formed in the part of the hemisphere opposite to the sun by the refraction and reflection of the sun's rays in drops of falling rain. Note: Besides the ordinary bow, called also primary rainbow, which is formed by two refractions and one reflection, there is also another often seen exterior to it, called the secondary rainbow, concentric with the first, and separated from it by a small interval. It is formed by two refractions and two reflections, is much fainter than the primary bow, and has its colors arranged in the reverse order from those of the latter. {Lunar rainbow}, a fainter arch or rainbow, formed by the moon. {Marine rainbow}, or {Sea bow}, a similar bow seen in the spray of waves at sea. {Rainbow trout} (Zo["o]l.), a bright-colored trout ({Salmoirideus}), native of the mountains of California, but now extensively introduced into the Eastern States. Japan, and other countries; -- called also {brook trout}, {mountain trout}, and {golden trout}. {Rainbow wrasse}. (Zo["o]l.) See under {Wrasse}. {Supernumerary rainbow}, a smaller bow, usually of red and green colors only, sometimes seen within the primary or without the secondary rainbow, and in contact with them.

Morse code: .-. .- .. -. -... --- .--