bluegrass

noun

Etymology: From the band Blue Grass Boys, led by Bill Monroe; bluegrass is first attested in print in reference to the genre of music in 1956.

1. A subgenre of country music with roots in Scots-Irish Appalachian folk music, blues, and jazz and characterized by banjos, fiddles, acoustic guitars, dobros, and mandolins; but containing no drums, electric guitars, pianos or other keyboard or wind instruments; using a bass fiddle to carry its rhythm.