Duke Ellington and Billy Strayhorn, “Satin Doll” 

This Jazz standard has been recorded by countless artists, becoming a well-established instrumental piece before Johnny Mercer wrote its clever lyrics. It is included here due to its use of a sonority that shares three of its notes with the Neapolitan, yet it functions quite differently in the context of Jazz and popular music. This sonority is understood as a Tritone Substitution (T.S.) chord built on ♭2 ˆ .