2.Blues a song sung or composed in a style originating among the American blacks,characterized typically by the use of three-line stanzas in which the words of the second line repeat the first The music is slow,expressing a mood of longing and melancholy.2. Blues : a song sung or composed in a style originating among the American blacks, characterized typically by the use of three-line stanzas in which the words of the second line repeat the first . The music is slow, expressing a mood of longing and melancholy