Blue is defined as the color between green and indigo in the rainbow that looks like the clear daytime sky.(noun)
An example of blue is the color of the Internet Explorer icon.
The definition of blue is having the color that looks like a clear day sky or being sad.(adjective)
See blue in Webster's New World College Dictionary
Origin: infl. by ME blo < ON blā, lividlivid: said of the skin
Origin: ME & OFr bleu < Frank *blao < IE base *bhlē-wos, light-colored, blue, blond, yellow > L flavus, yellow, Brythonic blawr, gray, OE blæwen, blue, Ger blau
See blue in American Heritage Dictionary 4
Origin: Middle English blue, bleu
Origin: , from Old French bleu
Origin: , of Germanic origin; see bhel-1 in Indo-European roots.
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