blue / blues
The adjective blue has been associated with despondency and sadness since the 16th century. The noun the blues has been with us since 1741, when English actor David Garrick penned the following in a letter:
I am far from being quite well, tho not troubled wth ye Blews as I have been.
The blues is a shortening of blue devils, demons popularly thought to cause depression and sadness. Blue devils have been around since at least 1616, from Times’ Whistle, a collection of satirical poems from that year:
Alston, whose life hath been accounted evill, And therfore cal’de by many the blew devill.
The glossary to that work has an entry for:
Devil, blew devill, 107/3443. “Blue devils,” the “horrors,” or the remorse which frequently follows an ill course of life.
The name of the musical style has been around since 1912, taking its name from the mournful and haunting nature of the lyrics. Some sources say the style takes its name from the blue notes that it uses, blue notes being a minor interval in place of a major, an off-pitch note. But the opposite is true. Blue notes get their name from the blues, not the other way around. Blue note is attested to in 1919.
(Source: Oxford English Dictionary, 2nd Edition; Google Books)
Copyright 1997-2016, by David Wilton