of, relating to, or shaped like a triangle; having three angles; triangular. 2. Crystallography. having threefold symmetry. Origin of trigonal.
An online survey conducted in the U.S. points out that the most popular music genre in the U.S. is rock, with 40 percent of respondents choosing this option. The second and third most listened to music genres are oldies and country respectively, while hip hop/rap is favored by a smaller niche of American listeners.
Rock music is a genre of popular music that originated as  rock and roll  in the United States in the 1950s, and developed into a range of different styles in the 1960s and later, particularly in the United Kingdom and the United States.ifferent subgenres of rock were adopted by, and became central to, the identity of a large number of sub-cultures. In the 1950s and 1960s, respectively, British youths adopted the Teddy Boy and Rocker subcultures, which revolved around US rock and roll.