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English definition of “rainbow”


noun [C]     /ˈreɪn.bəʊ/ US  /-boʊ/
B2 an arch (= curved shape ) of different colours seen in the sky when rain is falling and the sun is shining : The tropical butterfly's wings were shimmering with all the colours of the rainbow.Rain
(Definition of rainbow noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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