mainstreamсуществительное The ideas, attitudes, or activities that are regarded as normal or conventional; the dominant trend in opinion, fashion, or the arts. The band's music has become part of the mainstream, appealing to a wide audience.
The principal or dominant course, tendency, or trend. Environmental concerns have entered the mainstream of political debate.
The main current of a river or stream. The canoe drifted into the mainstream and picked up speed.