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English definition of “blue”

blue

adjective, noun [C/U]  /blu/ us  

blue adjective, noun [C/U] (COLOR)

(of) the color of the sky on a clear, bright day: She has blue eyes.
Idioms

blue

adjective [-er/-est only]  /blu/ us  

blue adjective [-er/-est only] (SAD)

sad; unhappy: I don’t know what’s wrong – I just feel blue.
(Definition of blue from the Cambridge Academic Content Dictionary © Cambridge University Press)
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