A barbershop song is a type of a cappella music that originated in the United States in the late 19th century. It is characterized by four-part harmony, with a lead vocalist singing the melody, a tenor singing above the melody, a bass singing below the melody, and a baritone singing between the lead and bass. The term 'barbershop' comes from the fact that these songs were often sung in barbershops. The answer to the crossword for the term 'barbershop song' is GLEE.