In the English language, blue implies speed in “a blue streak”（一闪而过的东西，形容很快的人或物）and loyalty in being “true blue.” Actual automobile values are found in a “blue book,” and a blue ribbon represents the award of excellence.
Blue may refer to the feeling of sadness, as in “he was feeling blue.” This is because blue was related to rain, or storms, and in Greek mythology, the god Zeus would make rain when he was sad (crying), and a storm when he was angry.
The phrase “feeling blue” is also linked to a custom among many old deepwater sailing ships — if the ship lost the captain or any of the officers during its voyage, she would fly blue flags and have a blue band painted along her entire hull（n.船 体）when returning to home port.
The modern English word blue comes from the Middle English, bleu or blwe, which came from an Old French word bleu of Germanic origin — Frankish or possibly Old High German blao, “shining.”
在英语中，用蓝色表示速度为“a blue streak”，表示忠诚为“true blue”。汽车实际价值的查询是在“蓝皮书”中，蓝丝带则代表优秀。
蓝色也可指代心情沮丧，如“he was feeling blue（他心情不好）”。因为蓝色与雨或暴风雨有关，在希腊神话中，宙斯在伤心时会降雨，生气时会有暴风雨。
词组“feeling blue”也与关于旧帆船的风俗有关——如果在航海时船长或其他海上官员遇难，在返乡时，船上就会升起蓝旗，整艘船缠上蓝色的带子。
现代英语单词blue来源于中古英语，bleu或blwe，它们来源于古法语bleu，而其又以日耳曼——法兰克或古德语中的“shining”为起源。
