Denshi Jisho — Online Japanese dictionary

クール 1: cool (temperature, color, etc.);
2: cool (i.e. calm and collected);
3: cool (i.e. fashionable, attractive, etc.);
4: (Noun) course (of medical treatment) (ger: Kur);
5: season (series) of a television program (usu. 13 installments over a 3-month period) (fre: cours)
Common word, Na-adjective 
クールー kuru (degenerative brain disease usually associated with New Guinean cannabalism)
Noun 
クールビズ cool biz; cool business; business casual (Japanese Ministry of the Environment (MOE) campaign encouraging people to wear lighter clothes and for companies to set their air conditioners to 28C, etc.)
Noun 
クールカラー cool color
Noun 
クールジャズ cool jazz
Noun 
クールダウン cool down
Noun 
クールボックス cool-box
Noun 
クールアイランド cool island
Noun 

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