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cool (temperature, color, etc.)
cool (i.e. calm and collected); cool-headed; cold-hearted
cool (i.e. fashionable or stylish)
彼はクールな性格だ。
He has a cool personality.
夏でもクールな色合いの服を選ぶ。
Even in summer, I choose clothes with cool colors.
彼女のクールな対応に少し驚いた。
I was a bit surprised by her cool response.