ˈreɪnbəu n. & adj. --n. 1 an arch of colours (conventionally
red,
orange,
yellow,
green, blue,
indigo, violet) formed in
the sky (or
across a
cataract etc.)
opposite the
sun by
reflection,
twofold refraction,
and dispersion of the sun's rays in falling
rain or in spray or
mist. 2 a
similar effect formed by the moon's rays. --adj. many-coloured. ørainbow
lorikeet a
small brightly
coloured Polynesian parrot, Trichoglossus haematodus. rainbow
trout a
large trout, Salmo gairdneri, orig. of the
Pacific coast of N. America.
secondary rainbow an
additional arch
with the colours in
reverse order formed
inside or
outside a rainbow by twofold reflection and twofold refraction. [OE regnboga (as RAIN, BOW(1))]