Red: of a spectral hue beyond orange in the spectrum.
Orange: a globose reddish yellow edibile citrus fruit of which there are two principle kinds, the bitter and sweet, the latter compromising the most important of the citrus fruits.
Yellow: a bright colour like that of butter, lemons, etc.; between green and orange in the spectrum.
Green: of the colour of growing foliage, between yellow and blue in the spectrum.
Blue: the pure hue of clear sky.
Indigo: a blue dye obtained from various plants, esp of the genus Indigofera.
Violet: any plant of the genus Viola, comprising chiefly low, stemless or leafy-stemmed herbs with purple, blue, yellow, white or variegated flowers, as V. hederacea and V. odorata, the much cultivated English Violet.
—From the Macquire Dictionary, 1990.
Beautiful.