If you've got the blues, you probably want to lie in bed and cry — or get out your guitar and sadly sing the blues.
Since the fourteenth century, the word blue has been used to mean "sad." The noun blues came into use in the 1700s to describe a state of sadness or melancholy. Around a hundred years later, a Black American musical genre adopted the word to describe its particular twelve-bar chord progression and folksy sound. Lyrics in blues music often describe hard times, struggles, and a particular kind of melancholy mood.