rainbow
UK[ˈreɪn.bəʊ]US[ˈreɪn.boʊ]
n
an arch of colors visible in the sky, caused by the refraction and dispersion of the sun's light by rain or other water droplets in the atmosphere.
n
a wide variety or range of related things.
Etymology
the word 'rainbow' is a classic english compound, directly inherited from old english 'regnboga'. its first element, 'regn', derives from proto-germanic regna-, meaning "rain", which is itself from the proto-indo-European root reg-, conveying the sense of "moist, wet". the second element, 'boga', meaning "bow" or "arch", comes from proto-germanic bugon-, from the pie root bheug- "to bend". the literal meaning, "rain-bow", perfectly captures the visual phenomenon—an arch that appears during or after rain. this transparent, descriptive logic has remained consistent from its ancient germanic origins to its modern usage, where it can also metaphorically describe any diverse spectrum.
Analysis
this is a compound word formed from two old english elements: 'regn' (rain) and 'boga' (bow, arch). it is a tight germanic compound where the individual morphemes are not independent in modern english spelling.
Examples
after the storm, a brilliant rainbow appeared over the hills.
the festival was a rainbow of cultures, with music and food from around the world.
the prism split the beam of light into a rainbow of colors.